solid state relays - sprecher + schuh · a solid state relay. units should not be mounted in an...

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Solid State Relays

General Description and Quick Selection Guide ..........................................E2

Series SAS Panel Mount “Hockey Puck” Relays...........................................E4

Series SAR DIN-Rail Mount Relays ..............................................................E6

Accessories ...............................................................................................E10

Application Notes .......................................................................................E12

Technical Information .................................................................................E20

Wiring Diagrams ........................................................................................E22

Dimensions ................................................................................................E23

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Series SAS(R)Solid StateRelays

Reliable performance for millions of operations up to 100 amps

Sprecher + Schuh’s SA line of solid state relays are the ideal solution for applications where high speed switching and long life are essential. In specific applications, solid state relays offer many advantages over electromechanical devices including no moving parts or contact arcing. In addition, solid state relays are directly compatible with logic components such as microprocessors and PLCs.

Broad selection for many applicationsSprecher + Schuh solid state relays are available in single phase “hockey puck” models up to 75 amps and DIN-rail mount units with integral heatsink up to 100 amps. Three phase models up to 25 amps are also available.

Opto-isolated input limits current leakageAll Series SA solid state relays feature opto-isolated inputs where an internal LED signals a photosensitive element when output switching is to occur. This provides up to 4,000V isolation between the input voltage and the output voltage and also limits current leakage. This feature is important in certain medical, residential and indus-trial applications. DC relays are also protected if the polarity is accidentally reversed during installation.

Benefits of SAS(R) Relays• HighPerformance• Directbondedcoppertechnology• 100%Tested• Zero-crossing• Outputvoltagesto660VAC• ACorDCcontrolsignalsand

AC output relays• Compact,innovativedesigns• UL/CSA/CE

Common ApplicationsSolid State Relays are used in a variety of commercial and industrial applica-tions, such as the following examples.

• HeatingControls• IndustrialProcessControls• InductionFurnaces• LaundryEquipment• PlasticMolding&Extrusions• PizzaOvens• ATMMachines• EggIncubators

Common ApplicationsHeating controls

Injection molding machines

Semiconductor manufacturing equipment

Glass processing

Welding controls

Food processing

Industrial & commercial ovens

Soldering machines

Medical equipment

Office machinery

Robotics

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Many safety and convenience featuresAll Sprecher + Schuh solid state relays come standard with an LED to indi-cate when the relay is in an operational state. This increases safety and speeds troubleshooting.

In addition, all hockey puck type re-lays come standard with a transparent cover that provides touch protection. Rail mounted relays also offer touch protection through the use of recessed terminals

Integral heatsink with DIN-rail mountingA complete selection of relays is avail-able with a built-in heatsink (SAR models). This eliminates the hassle of selecting and installing a properly sizedheatsink,ormountingtherelaydirectly on the back pan with silicone grease.

“Intelligent” relays include special fusingLargerSARrelays(50,75&100A)come standard with a feature that shuts down the unit when it senses an over temperature condition. A built-in replaceable semiconductor fuse further protects these larger relays from cata-strophic failures due to short circuits.

International standards and approvalsSeriesSASolidStateRelaysareULRecognizedandCSAApproved.TheyalsocarrytheCEMark,makingthemidealforequipmentthatwillbeexported to the European Economic Community.

➊ Omit “D” from catalog number if selecting AC control. Example: SAS(R)3-25-1D becomes SAS(R)3-25-1

Quick Selection GuideSurface Mount (hockey puck) Relays

SA S 3 50 1 D See Page...Type Mounting Output Voltage Amp Range Poles Control Voltage

S Surface Mount (hockey puck) 3 330V maximum 10 1 D 4-32V DC E4205075

S Surface Mount (hockey puck) 3 330V maximum 10 1 ~ 100-280V AC ➊ E4205075

S Surface Mount (hockey puck) 6 660V maximum 50 1 D 4-32V DC E575

S Surface Mount (hockey puck) 6 660V maximum 50 1 ~ 100-280V AC ➊ E575

DIN-rail Mount Relays (with integral heatsink)

SA R 6 25 1 D See Page...Type Mounting Output Voltage Amp Range Poles Control Voltage

R Rail mount (with integral heatsink) 6 660V maximum 25 1 D 4-32V DC E640 E650 1 D 4-28V DC E875 E8100 E9

R Rail mount (with integral heatsink) 6 660V maximum 50 1 ~ 100-280V AC ➊ E875 E8100 E9

R Rail mount (with integral heatsink) 6 660V maximum 25 3 D 4-28V DC E10R Rail mount (with integral heatsink) 6 660V maximum 25 3 ~ 100-280V AC ➊ E10

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SAS

1 Pole Panel Mount Relay, 4-32V DC Control, 330VAC Max. Output ➊ ➋

Solid State RelaysSeries SAS Panel Mount Relays

Specifications 10 Amp 25 Amp 50 Amp 75 Amp

Catalog Number Price Catalog Number Price Catalog Number Price Catalog Number Price

SAS3-10-1D 45 SAS3-25-1D 50 SAS3-50-1D 79 SAS3-75-1D 104

InputVoltage Range 4 - 32V DC 4 - 32V DC 4 - 32V DC 4 - 28V DCCurrent Draw 5.4-10mA 5.4-10mA 3.5-8mA 3.5-8mATurn-on Voltage (min.) 4V DC 4V DC 4V DC 4V DCTurn-off Voltage (max.) 1V DC 1V DC 1V DC 1V DC

OutputAmp Rating (continuous with proper heatsink) 10 25 50 75Voltage Range 24 - 330V AC 24 - 330V AC 24 - 330V AC 24 - 330V ACFrequency Range 47 - 63 Hz 47 - 63 Hz 47 - 63 Hz 47 - 63 HzDimension (mm) 57(H) x 44.5(W) x 35(D) With safety cover 57(H) x 44.5(W) x 23(D) Without safety cover

1 Pole Panel Mount Relay, 100-280V AC Control, 330VAC Max. Output ➊ ➋

Specifications 10 Amp 25 Amp 50 Amp 75 Amp

Catalog Number Price Catalog Number Price Catalog Number Price Catalog Number Price

SAS3-10-1 53 SAS3-25-1 55 SAS3-50-1 88 SAS3-75-1 112

InputVoltage Range 100 - 280V AC 100 - 280V AC 100 - 280V AC 100 - 280V ACTurn-Off Current/Impedance 2mA/10k 2mA/10k 2mA/10k 2mA/10kTurn-on Voltage (min.) 100V AC 100V AC 100V AC 100V ACTurn-off Voltage (max.) 20V AC 20V AC 20V AC 20V AC

OutputAmp Rating (continuous with proper heatsink) 10 25 50 75Voltage Range 24 - 330V AC 24 - 330V AC 24 - 330V AC 24 - 330V ACFrequency Range 47 - 63 Hz 47 - 63 Hz 47 - 63 Hz 47 - 63 HzDimension (mm) 57(H) x 44.5(W) x 23(D) Without safety cover 57(H) x 44.5(W) x 35(D) With safety cover

Safety Cover (included)


➊ See important application considerations on next page. ➋ Safety cover and terminal screws/saddle clamps supplied with SAS unit.

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SAS

Solid State RelaysSeries SAS Panel Mount Relays

1 Pole Panel Mount Relay, 4-32V DC Control, 660VAC Max. Output ➊

Specifications 50 Amp 75 Amp

Catalog Number Price Catalog Number Price

SAS6-50-1D 96 SAS6-75-1D 134

InputVoltage Range 4 - 32V DC 4 - 32V DCCurrent Draw 3.5...8mA 3.5...8mATurn-on Voltage (min.) 4V DC 4V DCTurn-off Voltage (max.) 1V DC 1V DC

OutputAmp Rating (continuous with proper heatsink) 50 75Voltage Range 24 - 660V AC 24 - 660V ACFrequency Range 47 - 63 Hz 47 - 63 HzDimension (mm) 57(H) x 44.5(W) x 23(D) no cover; 57(H) X 44.5(W) x 35(D) with cover

1 Pole Panel Mount Relay, 100-280V AC Control, 660VAC Max. Output]

Specifications 50 Amp 75 Amp


SAS6-50-1 104 SAS6-75-1 145

InputVoltage Range 100 - 280V AC 100 - 280V ACTurn-off Current/Impedance 2mA/10k 2mA/10kTurn-on Voltage (min.) 100V AC 100V ACTurn-off Voltage (max.) 20V AC 20V AC

OutputAmp Rating (continuous with proper heatsink) 50 75Voltage Range 24 -660V AC 24 - 660V ACFrequency Range 47 - 63 Hz 47 - 63 HzDimension (mm) 57(H) x 44.5(W) x 23(D) no cover; 57(H) X 44.5(W) x 35(D) with cover



Important Note:SAS FamilyAdequate heat sinking, including con-sideration of air temperature and flow, is essential to the proper operation of a solid state relay. Units should not be mounted in an enclosed area without proper air flow. Units should also never be mounted to a plastic base or to a painted surface. Failure to provide ad-equate heat sinking with thermal gel or pad will cause a solid state relay to fail.

Engineering Note: All units must be correctly installed on an appropriate heat sink, with a thermal transfer gel or pad, in order to dissipate the heat generated. See pages E12, E14 and E15 for more details.

➊ Safety cover and terminal screws/saddle clamps supplied with SAS unit.

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SAR

Relay base temperature (ºC)

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25A

Ambient temperature (°C), measured 1” (25mm) below relay when mounted on a vertical surface


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40A

Ambient temperature (°C), measured 1” (25mm) below relay when mounted on a vertical surface 25 Amp 40 Amp


Specifications SAR6-25-1D 111 SAR6-40-1D 134

InputVoltage Range 4 - 32V DC 4 - 32V DCCurrent Draw 3.5...8mA 3.5...8mATurn-on Voltage (min.) 4V DC 4V DCTurn-off Voltage (max.) 1V DC 1V DC

OutputAmp Rating (continuous with proper air flow) 25 40Voltage Range 24 - 660V AC 24 - 660V ACFrequency Range 47 - 63 Hz 47 - 63 HzDimension (mm) 87(H) x 30(W) x 100(D) 87(H) x 60(W) x 100(D)

1 Pole DIN-Rail Mount Relay, 100-280V AC Control, 660VAC Max. Output


30

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Ambient temperature (°C), measured 1” (25mm) below relay when mounted on a vertical surface


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Ambient temperature (°C), measured 1” (25mm) below relay when mounted on a vertical surface 25 Amp 40 Amp


Specifications SAR6-25-1 117 SAR6-40-1 147

InputVoltage Range 100 - 280V AC 100 - 280V ACCurrent Draw 9...25mA 9...25mATurn-off Current/Impedance 2ma/10kΩ 2ma/10kΩTurn-on Voltage (min.) 90V AC 90V ACTurn-off Voltage (max.) 20V AC 20V AC


1 Pole DIN-Rail Mount Relay, 4-32V DC Control, 660VAC Max. Output

Solid State RelaysSeries SAR

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SAR

Solid State RelaysSeries SAR DIN-rail Mounted Relays


50 Amp 75 Amp


Specifications SAR6-50-1D 242 SAR6-75-1D 358

InputVoltage Range 4 - 28V DC 4 - 28V DCCurrent Draw 6...9mA 6...9mATurn-on Voltage (min.) 4V DC 4V DCTurn-off Voltage (max.) 1V DC 1V DC



50 Amp 75 Amp


Specifications SAR6-50-1 250 SAR6-75-1 366

InputVoltage Range 100 - 280V AC 100 - 280V ACCurrent Draw 5...15mA 5...15mATurn-off Current/Impedance 2mA/10kΩ 2mA/10kΩTurn-on Voltage (min.) 100V AC 100V ACTurn-off Voltage (max.) 20V AC 20V AC


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SAR



100 Amp

Catalog Number Price

Specifications SAR6-100-1D 633

InputVoltage Range 4 - 28V DCCurrent Draw 6...9mATurn-on Voltage (min.) 4V DCTurn-off Voltage (max.) 1V DC

OutputAmp Rating (continuous with proper heatsink) 100Voltage Range 48 - 660V ACFrequency Range 47 - 63 HzDimension (mm) 126(H) x 120(W) x 128(D)


100 Amp


Specifications SAR6-100-1 646

InputVoltage Range 100 - 280V ACCurrent Draw 5...15mATurn-off Current/Impedance 2mA/10kΩTurn-on Voltage (min.) 100V ACTurn-off Voltage (max.) 20V AC

OutputAmp Rating (continuous with proper heatsink) 100Voltage Range 48 - 660V ACFrequency Range 47 - 63 HzDimension (mm) 126(H) x 120(W) x 128(D)

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SAR



Ambient temperature (°C), measured 1 inch (25mm) below relay when mounted to DIN rail or a vertical, 1/8th inch thick aluminum panel

surface. Airflow is unrestricted up and through the heat sink.

25 Amp


Specifications SAR6-30-3D 285

InputVoltage Range 4 - 32V DCCurrent Draw 10...15mATurn-on Voltage (min.) 4V DCTurn-off Voltage (max..) 1V DC

OutputAmp Rating (continuous with proper air flow) 25 A (3 Pole) 30 A (2 Pole)Voltage Range 48 - 660V ACFrequency Range 47 - 63 HzDimension (mm) 87(H) x 90(W) x 100(D)


Ambient temperature (°C), measured 1 inch (25mm) below relay when mounted to DIN rail or a vertical, 1/8th inch thick aluminum panel

surface. Airflow is unrestricted up and through the heat sink.

25 Amp


Specifications SAR6-30-3 300

InputVoltage Range 100 - 280V ACCurrent Draw 9...30mATurn-off Current/Impedance 2mA/10kΩTurn-on Voltage (min.) 100 0V ACTurn-off Voltage (max..) 20V AC

OutputAmp Rating (continuous with proper air flow) 25 A (3 Pole) 30 A (2 Pole)Voltage Range 48 - 660V ACFrequency Range 47 - 63 HzDimension (mm) 87(H) x 90(W) x 100(D)

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Solid State RelaysSeries SAS(R)

Replacement PartsPart Description Catalog Number Price

Replacement Semiconductor Fuses- One fuse supplied standard with each fused relay.

Fuse Size Fits Relay...

63A SAR6-50-1 SA-SFU-63 84SAR6-50-1D

100A SAR6-75-1 SA-SFU-100 94SAR6-75-1DSAR6-100-1SAR6-100-1D

Replacement Cover - One cover supplied standard with each SAS panel mount relay.

SA-SC1 5

AccessoriesAccessory Description Catalog Number Price

DIN-rail - 2 meter lengths (6’6”)Top Hat, low profile (price per rail)Top Hat, high profile (package of 20, price per rail)

3F3AF

See page A58

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SAS

AccessoriesAccessory Description Catalog Number Price

Heatsink –

50

Panel or DIN-rail mount for mounting one SAS relay.

For most 35-60A applications 1.0 C/W capability

SAS-HTSK-1.0

Heatsink –

33

Panel or DIN-rail mount for mounting one SAS relay.


SAS-HTSK-1.6

Heatsink –

135

Panel or DIN-rail mount for mounting up to six SAS relays.


SAS-HTSK-1.2

Thermal Transfer PadsOur thermal transfer pads are die-cut to fit the bases of Sprecher + Schuh panel mount relays. They are an excellent replacement for thermal greases, and are proven to provide the lowest thermal resistance values of any commercially practical interfacematerial, while being more convenient and less messy. Available in sets of 5.

• 60°CPhaseChangeTemperature• TotalInterfacePadThickness=3mils• LowestContactThermalImpedanceAvailable• No“runout”inverticalmountingapplications• Heatsensitivematerial,storebelow30°C(85°F)• Ruggedizedmaterialthatisresistanttohandling damage while in transit

Sold in packages of 5 pieces

Catalog NumberPKG Price

SAS-THERMPAD5 20

How to calculate the proper size heat sink?As ambient temperature increases, the use of a properly sized heat sink becomes necessary. Hint: the smaller the “heat sink rating” number, the better the heat sink is at dissipating the heat. The new DIN heat sinks are the outstand-ing choice for most applications because:

1) They use the least amount of sub-plate mounting space,

2) They extend the heat sink forward for the best air flow, and

3) Universal mounting-bracket -they can be DIN rail-mounted for fast installations without the need for drilling and tapping pre-aligned hole patterns, or they can be attached with a standard bolt.

Use a thermal conduction grease or a thermal pad in order to achieve the proper heat sinking capability between the SSR and the heat sinks show below:

SAS-HTSK Features/Benefits:l DIN rail mountablel Space saving designl Ground screw built-inl Drilled and tapped to fit panel mount relays

Solid State RelaysSeries SAS Solid State Relays

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General Application Notes

Heat SinkingHeat is generated by all Solid State Relays in direct relation to the amount of current being switched. Approximately 0.8-1.4 Watts will be generated by the SSR for every Amp switched. This heat must be dissipated as fast as generated otherwise the temperature will increase until the relay fails. Approximately 90% of all prob-lems with relays are directly related to heat.Adequate heat sinking, including consideration of air tempera-ture and flow, is essential to the proper operation of a solid state relay. Units should never be mounted in an enclosed area without proper air flow. Units should also never be mounted to a plastic base or to a painted surface. Failure to provide adequate heat sinking will cause a solid state relay to fail. We recommend mounting our units on the heat sinks listed on page E12 of this catalog. However, when this is not possible, and the units are to be mounted to some other heat sinking object, material heat con-ductivity should be kept in mind. In heat dissipation, our heat sinks are approximately equivalent to a sheet of aluminum 1/8” thick by the dimensions shown:

SAS-HTSK-1.6 10” x 10” (254 x 254mm)SAS-HTSK-1.0 14” x 14” (355.6 x 55.6mm)

(Given proper ventilation and ambient temperature.)

In comparison, twice the amount of steel and four times the amount of stainless steel would be needed to achieve the same effect.

Any panel mount Solid State Relay must be mounted to a clean, bare (non-painted) surface that is free of oxidation.

Since even the best heat sink surfaces have some imperfections, there will be many air pockets between the base of the relay and the heat sink (or panel) surface.

Air is a very poor conductor of heat and will cause the relay to run hotter than it should. To fill these pockets, Thermal Transfer Pads (see pg E12) should be placed on the metal base of the relay before mounting to a metal surface. We suggest torque of 10 inch-pounds on both of the SSR mounting screws.

Alternately, an evenly applied 0.002” thick layer of Dow Corn-ing 340 (or equivalent) can be used. Note that a thicker layer of thermal compound actually decreases heat transmission.

Since airflow will affect its performance, a heat sink should be mounted in a manner that assures unrestricted airflow over its surface. Recommended mounting is on a vertical metal surface, with the fins oriented vertically so that air can flow unimpeded along the surfaces of the heat sink. Horizontal or inverted mount-

Application NotesSeries SA Solid State Relays

ing is possible but not recommended, and the SSR must be derated accordingly.

Care must be taken when mounting multiple SSRs in a con-fined area. SSRs should be mounted on individual heat sinks whenever possible. Panel mount SSRs should never be operated without proper heat sinking or in free air as they will THERMALLY SELF DESTRUCT UNDER LOAD.

A simple method for monitoring temperature is to slip a ther-mocouple under a mounting screw. If the base temperature does not exceed the “max heat sink temperature” (shown on pg E14) under normal operating conditions, the SSR is operating in an optimal thermal environment. If this temperature is exceeded, the relays current handling ability must either be thermally im-proved by the use of a larger heat sink, or greater air flow must be provided over the device through the use of a fan. Some cases may require the selection of a higher current output SSR and thermally derating the device accordingly.

Remember that the heat sink removes the heat from the Solid State Relay and transfers that heat to the air in the electrical enclosure. In turn, this air must circulate and transfer its heat to the outside ambient. Providing vents and/or forced ventilation is a good way to accomplish this.

80% Power RuleAll Solid State Relays are capable of running at full rated power (with proper heat sinking). However, it is strongly suggested that they be used at no more than 80% power to provide a safety margin in case of higher than expected voltage, tempera-ture, or dust on the heat sink, etc. Additionally, voltage can vary up to +/-10%, and a heating element up to +/-10% over its life—two main reasons for the 80% rule.

Din Mounted Single and Three Phase RelaysThe SAR series are provided with integral heat sinks. The SAR50-100A units should be mounted so as to provide 1” (25mm) of space between the units, for best air flow (the 80% of power rule described above still applies). They can be mounted against each other if the end units in a row are derated by 10% and the middle units are derated 10% more than the end ones.

On the other hand, the SAR-25/40A units can be installed on a DIN-rail with only 0.18 inches between relays, “Fin-to-Fin”! The SAR-25/40A family provides more amps per square inch than other brands of industrially hardened SCR controllers and

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General Application Notes (continued)


will perform better in installations with higher ambient tempera-tures.

For proper airflow, the SAR units should both be mounted in a manner leaving space above and below the heat sink equal to or greater than the height of the heatsink. Since airflow will affect performance, relays with integral heat sinks should be mounted in a manner providing unrestricted airflow over their surfaces. Recommended mounting is on a vertical surface, with the fins ori-ented vertically, so that air can flow unimpeded along the surfaces of the heat sink.

Heat Sink Calculations for SAS Family of Solid State RelaysSprecher + Schuh SAS Power Dissipation

SAS3-10 SAS3-2510 Amp Relays 25 Amp Relays

10A/11W 25A/31W8A/9W 20A/23W6A/6W 15A/16W4A/4W 10A/10W2A/2W 5A/5W

Max heat sink=90ºC Max heat sink=85ºCPwr Ref: VO=0.80VO Pwr Ref: VO=0.80VO

Rt=0.038 Ω Rt=0.021 Ω

SASx-50 SASx-7550 Amp Relays 75 Amp Relays

50A/59W 75A/84W40A/44W 60A/63W30A/30W 45A/44W20A/18W 30A/27W10A/9W 15A/13W

Max heat sink=105ºC Max heat sink=105ºCPwr Ref: VO=0.80VO Pwr Ref: VO=0.85VO

Rt=0.0092 Ω Rt=0.0046 Ω

All calculations are in ºC. See derating curves on next page. Sprecher + Schuh provides three ways to calculate the heat sink for your application.

1) Heat Sink Calculation Method

Maximum heat sink temperature minus maximum ambient tem-perature divided by the power dissipation (use the chart above for power dissipation at desired current).

(Max Heat Sink Temp - Max Ambient Temp) / Watts = ___For Example, use an

• SAS3-25-1Drunningat20Ampsina45ºCambient• Fromthechart,at20Ampsitdissipates23Watts

• A25Aunitcanhavean85ºCheatsink• (85-45ambient)=40ºCtempriseisallowed• 40ºC/23W=1.74ºC/Wheatsinkratingorless (less temperature rise per watt is better)• Therefore,therecommendedheatsinkwouldbepart

number: SAS-HTSK-1.6 (rated at 1.6ºC/W) or any equivalentheatsinkthatis1.74orLESS.Remember,the lower the heat sink value, the better it dissipates the heat. The relay must be connected to the heat sink using an appropriate thermal conduction grease or thermal pad.

2) De-Rating Calculation Method

Maximum heat sink temperature minus maximum ambient temperature divided by the heat sink rating (use the previous chart for power dissipation).

(Max Heat Sink Temp - Max Ambient Temp) / Heat sink rating = ___(Max allowed Watts)For Example, use an

• SAS3-10-1Disa60ºCambientwitha 2.0ºC/W heat sink.• 90ºC-60ºC=30ºCheatsink Temperature rise is allowed.• 30ºCdividedby2.0ºC/W=15W.• Fromthetable,fullloadcurrentof 10A only dissipates 11W.• Thus,anSAS3-10-1Dmountedona 2.0ºC/W heat sink can switch 10A at 60ºC.

3) Power Calculation in Place of the Charts

Heat rise calculation of an SAS solid state relay based upon amperage switched “ON” 100% of the time. Please note, the Sprecher + Schuh “SAS” SSR uses engineering techniques that provide maximum surge survivability while generating a low temperature rise.

(0.9 x Irms x VO) + (I2rms≈ x Rt) = Power

For Example, use an • SAS3-25-1Dfora21Aapplication.• (0.9x21Ax0.80V)+(212x0.021Ω)=24.4W

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SAS Family Solid State Relay Power Curves

10 Amp Relay

RMS on-state current (amps)

25 Amp Relay


50 Amp Relay


75 Amp Relay


Motor Applications (SAR - 3 Phase Unit)The Sprecher + Schuh 3 phase solid state relay is designed for switching power to 3 phased asynchronous motors and to resistive loads. For guidance in its application, refer to the following notes:

(380 Volt, 50/60Hz Motors - Direct Start)

Motor Start OperatingSize Current Current(KW) (Arms) (Arms)

2-Pole - 3000 RPM 3 43.4 6.24-Pole - 1500 RPM 3 38.0 6.96-Pole - 1000 RPM 4 47.7 9.08-Pole - 750 RPM 3 36.6 8.7

(220 Volt, 50/60Hz Motors - Direct Start)

2-Pole - 3000 RPM 2.2 45.0 7.0

Overload CapacitiesIn the event that a load completely or partially short circuits, the following table indicates the absolute maximum current that the 3 Phase SAR-Unit relay can withstand for various time limits:

Time Current Time Current(Sec) (Arms) (Sec) (Arms)

.2 275 8.0 80

.4 228 10.0 75

.6 188 12.0 72

.8 161 14.0 711.0 150 16.0 702.0 124 18.0 694.0 95 20.0 676.0 86 40.0 58

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Three Phase Motor Control (SAS Series)Three phase motors can be controlled as shown. Note that only two SSRs are required (the third is optional). The inputs are shown in parallel, but they can also be connected in series as long as the minimum control voltage is provided to power each relay.

Three Phase Wiring SuggestionsRelay positioning in a three-phase circuit impacts the current draw and therefore the amount of heat generated. When po-sitioned in location “A”, as indicated below, a relay will draw 73.2%morecurrentthanposition“B”.Usingposition“B”willenable the use of a smaller relay or will provide an increased safety margin. Additionally, by drawing less current, heat generation is reduced by 40%.

Example Wiring (SAR-3 Phase Unit)

Logic Signal (TTL) OperationOne of the primary advantages of SSRs and I/O modules is their compatibility with low level, solid state logic. Any logic gate, buffered or not, capable of delivering the required current and voltage within its maximum power dissipation rating can be used to control an SSR or I/O module.

Many TTL gates, for example, will safely dissipate 40mW or more; and the total package will dissipate up to one Watt. (This gate power must not be confused with relay input power.) WhereasanSSRinwhichtheinputrequires6mAat5Vdccon-sumes 30mW of power, the TTL gate sinking this same 6mA may have a voltage drop of only 0.2 volt, and power consumption of just 1.2 mW!

TTL gates can only sink relay input current, not source it. This is because the sourcing transistor has a pull-up resistance in its col-lector circuit. Pulling 11mA through this resistance, in this case 130 ohms, would leave insufficient input voltage to operate the relay.Forexample,anSSRrequiringanominal5Vdcmaynotoperate on less than 4 volts.

Typically, the drop across the transistor and diode at 11mA would approximate 0.8 volt; and the drop across 130 ohms is 1.4 volt. This 2.2 volt drop would leave only about 1.8 volts for the relay to operate, not enough for relay turn-on.

Since TTL gates can only sink current to the relay, and since cur-rent sinking is done from a “zero” logic signal, the relay can only be turned on from a “zero” signal. This is contrary to normal relay operation, which prefers that the relay be turned on as a result of a “one” signal. To obtain relay actuation from a logical “one” signal, it is necessary to use an inverting gate. With such a gate, when a “one” signal is received, the sink transistor will turn on and conduct relay input current.

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Changing Pickup and Dropout VoltageByusingazenerdiodeinserieswiththeinput,thepickupanddropout voltage of a Solid State Relay or an I/O Module can be increased by the value of the zener. For example, a typical SSR has a maximum pickupvoltageof4Vdcandaminimumdropoutof1Vdc.Byadd-ing a 6 volt zener as shown, the new pick up will be 10 volts and the newdropout7volts.

Latching SSRAn AC SSR can be made to self latch (at the sacrifice of input-output isolation), thus permitting the use of momentary action switches for on/off or stop/start operation. It may be necessary to insert an RC filter across the relay input to prevent the relay from turning on due to switching transients upon application of system power. Note that the SSR employed here must be an AC input type.

2.2k Ω, 5W

1k Ω, 5W

Installation DensityTo achieve maximum installation density and to provide separate wiring channels for the high voltage/high current wires vs the control signal wires, Sprecher + Schuh’s SAR family of 25 or 40 amp products can be installed as shown below. Please ensure that you observe the wire terminal numbers. The spacing shown is the minimum requirement for most industrial applications. Unrestricted airflow is needed for the Sprecher + Schuh product to perform at its rated capacity.

Crimped-on Wire TerminalsWhen using either Ring or Spade crimped terminals with the SAS relays, do not use the saddle clamps that are pro-vided. It is sufficient to secure the Ring or Spade Connec-tors with the enclosed screws.

When using electrical wire that is larger than #10 AWG with the SAR relays, 25-40 amp models, use a crimped lug, suchasAmp#790368-1orequivalent.

DIN Rail SizesAll DIN Rail mountable relays and modules will fit on any standard 35mm rail.



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Heater LoadsSolid State Relays are well suited for driving heaters, however, in some temperature control applications the load is rapidly and almost continuously switched on and off. This is ideal for purely resistive loads (0.9-1.0 power factor). For loads of power factor 0.8-0.9 Sprecher + Schuh recommends increas-ing the controller cycle time to 5 sec. minimum. Loads with a power factor <0.8 should be derated for inductive load.

Recommended Heater Loads:SSR at at at

Rating 120Vac 240Vac 480 Vac10A 960W 1.9KW 3.8KW25A 2.4KW 4.8KW 9.6KW50A 4.8KW 9.6KW 19.2KW75A 7.2KW 14.4 KW 28.8KW

Low cold resistance elements such as Tungsten or Short Wave Infrared have special design considerations due to high inrush currents. Please consult the factory.

Solenoid Valves and ContactorsAll of Sprecher + Schuh power SSRs use high noise immu-nity circuitry in addition to a snubber network to handle the electrical noise generated by inductive loads.However, the cycling of a solenoid load will generate large current spikes which will decrease the power capability of the SSR. The power rating of the SSR will be reduced by the power rating percentage shown.

Cycle Time Power Rating20 sec. 80%5 sec. 65%1 sec. 40%

RecommendedSolenoidLoads=VxIx(PowerRating)

Recommended Solenoid at 5 sec. cycle time.SSR at at

Rating 120Vac 240Vac10A 780W 1.9KW25A 2.0KW 3.9KW50A 3.8KW 7.6KW75A 5.8KW 14KW

Short Circuit ProtectionThe relay can be short circuit protected with an appropriate semiconductor fuse. The load integral of the relay (I2t) deter-mines which size of fuse is to be used. The fuse load integral must be below that of the relay for the appropriate protection. Becertaintoanalyzethefusecurrent/timecurvetoinsurethatthe fuse can withstand the motor starting current (if applicable).

NOTE: Overload protection should be provided by another slow-acting fuse in series with the short circuit protection fuse. (An overload being an overcurrent condition that is not of high enough amplitude to be considered a short circuit).

Transient Voltage ProtectionWhen operating a relay in an electrically noisy environment, large voltage transients may damage the relay. To protect against this occurrence, it is advisable to install appropriate varistors across the respective supply and load terminals of the relay output.

Model SAR6-30-3 shown with customer-installed MOVs.

If your application is located near inductive loads, or shares power sources with large inductive loads that are creating tran-sients in excess of the blocking voltage of the Sprecher + Schuh solid state relay, then you must install a metal oxide varistor (MOV)toprotectthesolidstaterelay.ItisuptotheinstallationcompanytoproperlysizetheMOVtotheapplication!Ideally,theMOVprotectionisnearthenoisegeneratinginductiveload(such as a motor, drive, or other large inductive coil) or you can placeMOVsdirectlyacrosstheoutputterminalsoftheSSR.Some“typical”MOVsinclude:

600voltapplication-HarrisV660LA80B480voltapplication-HarrisV575LA80B300voltapplication-HarrisV320LA40B

The new SAS and SAR families of solid state relays include tech-nology that dramatically reduces your need to install an external MOVexceptinextremelynoisyenvironmentsorinductiveloadapplications.



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Single Phase Motor ControlThe following table gives guidelines for selecting relays for single phase non-reversing motors. Driving reversing motors is not rec-ommended due to the potentially destructive voltage doubling and capacitive discharge that they create.

Recommended Loads:SSR at at at

Rating 120Vac 240Vac 480Vac10A 1/4 Hp 1/2 Hp -25A 1/3 Hp 1 Hp 2 Hp50A 3/4 Hp 2 Hp 3 Hp75A 1-1/4Hp 3 Hp 7-1/2 Hp

Lamp TestAn AC output solid state relay can be quickly and easily tested. To evaluate whether or not it is operative, connect the relay as follows using the appropriate voltages. The lamp bulb should not turn “On” until the control voltage is applied (and “Off” when control voltage is removed). If the lamp comes “On” with no con-trol voltage, the output is shorted.

Shown is an AC output solid state relay. DC units can be checked the same way with appropriate DC voltages and load.

SafetyDue to their leakage current Solid State Relays are NOT open circuits, even when in the off-state. Safety can only be achieved by a mechanical disconnect between the solid state relay and the power lines.

Typical Temperature Control InstallationElectrically heated chamber application:

• DCactivatedSAR6solidstaterelay• Thermocoupleinput• Alarmforoperatorwarning

Typical Temperature Control ApplicationPackaging or food processing application:

• SASDCactivatedsolidstaterelay• Analogsensorinput• AlarmcircuittostopPLCorrelatedequipment

Locking Screws - SAR UnitsScrews are prevented from self-loosening by a special design. The automatic progressive locking principle generates an increasing thread friction as the screw is tightened. Repeated tightening and loosening does not cause fatigue of the locking components.Recommendedtorqueis7-9in/lbs.Careshouldbe taken not to overtighten screws.



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Fusing ConsiderationsCircuitBreakersandslowblowfusesoffernoprotectiontoSolidstate relays. Fast, “I2T Semiconductor Fuses” are the only reliable way to protect SSRs.

All solid state relays have an I2T rating. This rating is the bench mark for their ability to handle a shorted output condition. Sprecher + Schuh advocates circuit protection through the use of a properly selected I2T (semiconductor fuse).

Devices such as electromechanical circuit breakers and slow blow fuses cannot react quickly enough to protect the SSR in a shorted condition and are not recommended!!

For fuses, I2T is the measure of let-through energy in terms of current versus time. For solid state relays, I2T is based directly on the output thyristor’s single-cycle peak surge current determined by:

I2T=I2pk(surge) x 0.0083 (sec)2

The procedure is to select a fuse with an I2T let-through rating that is less than the I2T capability of the solid state relay for the same duration.

An I2T fuse protects the solid state relay. You still need a regular fuse or circuit breaker to protect the complete installation, in accordance with your local electrical code.

Leakage - Effect on InputMany temperature controllers and PLC’s use triacs as output devices and most manufacturers place a “.022 microfared snub-ber” across their triacs for their own protection. This snubber can produce enough leakage when the controller is “off” to cause the solid state relay connected to it to go “on” or at least to not turn “off” properly.

A solution to this problem is to place a 10K ohm, 2 Watt resistor (for120Voltcontrol),acrosstheinput(control)ofthesolidstaterelay.

The SAS and SAR AC input family typically do NOT need the additional burden resistor. This saves you installation time and cost.

Output LeakageSolid state relays typically have 8mA leakage current, even in their off-state. The only safe way to prevent shock is to have a mechan-ical disconnect between the line and the relay.

Direct Copper BondingSprecher + Schuh employs the proven reliability of direct copper bonding technology to all of its SCR chip assemblies. This direct bonding provides a more reliable mechanical connection between the SCR and the heat sink, by reducing the physical stress on the chips and also provides for better heat dissipation by reducing the layers heat must travel through to the ambient. This results in a more durable relay and a longer usable relay lifetime.

Using SSRs with Electromechanical RelaysUsing an SAS or SAR relay to activate an electromechanical or mercury contactor is possible. Electromechanical relays produce a significant amount of electrical noise which could cause a solid state relay to mistrigger. If these two types of relays are used together, surge voltage protection may be required.

CautionSprecher+Schuh Solid State Relays can fail without warning (as is possible with any electronic component).

For this reason Sprecher+Schuh cannot recommend, condone or war-rant any application of our products that could cause harm or injury, in any manner, to any person upon such failure of the product.

Please contact the factory if you have any doubts or questions as to whether this caution applies to your application.



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SAS

Technical InformationSeries SAS Solid State Relays

Technical InformationSAS3-10-1(D) SAS3-25-1(D) SAS3-50-1(D) SAS3-75-1(D) SAS6-50-1(D) SAS6-75-1(D)

Performance DataInput

Voltage [V] 100-280V AC (4-32V DC)

Turn-on Voltage (min.) [V] 100V AC (4V DC)

Turn-on Current (min/max) [mA] (5.4...10) (3.5...8)

Turn-off Voltage (max.) [V] 20V AC / 2mA (1V DC)

Reverse Voltage Protection [V] Not applicable (-75V DC)

Impedance Rc [Ω] 20KΩ (1500Ω)

OutputRated Amps (IOUT) - continuous with proper heatsink

[ARMS] 10 25 50 75 50 50

Voltage Drop (IOUT) [VAC] 1.1 1.2 1.3 1.1 1.3 1.1

Surge Current Withstand

1 cycle, non-repetitive [APEAK] 100 250 650 950 650 9501 second, non-repetitive

[APEAK] 40 100 130 140 130 140

Voltage Range (VOUT) [VAC] 24-330 24-330 24-330 24-330 24-660 24-660

Peak Blocking Voltage [PIV] 800 800 800 800 1200 1200

Frequency Range [Hz] 47-63 47-63 47-63 47-63 47-63 47-63

Leakage (VOUT) Max. [mA] 8 8 8 8 8 8

Turn On (Max.) 1/2 cycle 1/2 cycle 1/2 cycle 1/2 cycle 1/2 cycle 1/2 cycle

Turn Off (Max.) 1/2 cycle 1/2 cycle 1/2 cycle 1/2 cycle 1/2 cycle 1/2 cycle

Holding Current (Min.) [mA] 50 50 50 50 50 50

Zero Voltage Switching V/µs Yes Yes Yes Yes Yes Yes

Dv/Dt (VOUT) Max. V/µs 750 750 1000 1000 500 500

Commutating Dv/Dt Snubbed for Power Factor = .5 .5 .5 .5 .5 .5

I2t Rating (8.3 ms) [A2S] 60 260 1620 7010 1620 7010

Thermal Resistance (R0JC) Tj-115ºC [ºC/W] 1.48 1.05 .65 .30 .65 .65

General Characteristics

Dielectric Strength (Input-Output-Base) [VRMS] 4000 4000 4000 4000 4000 4000

Capacitance Input to Output [pf] 3 3 3 3 3 3

Ambient Temperature Range (Operating) [ºC] 0...40ºC (up to 80ºC with derating)

SCR Technology Alternistor (Inv. Parallel SCRs) Inv. Parallel SCRs

Approvals UL Recognize (E175459), CSA, meets EN 60947-4-3

Mechanical Data

Terminal TypeControl 6-32 screw w/saddle clampPower 8-32 screw w/saddle clamp

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SAR

Technical InformationSeries SAR Solid State Relays

Technical InformationSAR6-25-1(D) SAR6-40-1(D) SAR6-50-1(D) SAR6-75-1(D) SAR6-100-1(D) SAR6-30-3(D)

Performance DataInput

Voltage [V] 100-280V AC(4-32V DC)

100-280V AC(4-28V DC)

100-280V AC(4-32V DC)

Turn-on Current (min/max) [mA] 9-25 (3.5-8) 5-15 (6-9) 9...30 (10-15)

Turn-on Voltage (min.) [V] 100 (4) 100 (4) 100 (4) 100 (4) 100 (4) 100 (4)

Turn-off Voltage (max.) [V] 20/2mA(1) 20/2mA(1) 20/2mA(1) 20/2mA(1) 20/2mA(1) 20/2mA(1)

Reverse Voltage Protection [V] N/A (-75) N/A (-75) N/A (-40) N/A (-40) N/A (-40) N/A (-75)

Impedance Rc [KΩ] 10 10 10 10 10 10

Output 25(3 pole)35 (2 pole)Rated Amps (IOUT) - continuous with proper heatsink [ARMS] 25 40 50 75 100

Voltage Drop (IOUT) [VAC] 1.0 1.2 1.3 1.3 1.3 1 per leg

Surge Current Withstand

1 cycle, non-repetitive [APEAK] 250 250 120 1500 2000 650

1 second, non-repetitive [APEAK] 100 150 200 300 400 130

Voltage Range (VOUT) [VAC] 48-660 48-660 48-660 24-660 24-660 24-660

Peak Block Voltage [PIV] 1400 1400 1200 1200 1200 1400

Frequency Range [Hz] 47-63 47-63 47-63 47-63 48-63 48-63

Leakage (VOUT) Max. [mA] 10 10 8 8 8 1

Turn On (Max.) 1/2 Hz 1/2 Hz 1/2 Hz 1/2 Hz 1/2 Hz 1/2 Hz

Turn Off (Max.) 1/2 Hz 1/2 Hz 1/2 Hz 1/2 Hz 1/2 Hz 1/2 Hz

Holding Current (Min.) [mA] 100 100 50 100 100 100

Zero Voltage Switching Yes Yes Yes Yes Yes Yes

Dv/Dt (VOUT) Max. V/µs 1000 1000 500 500 500 100

Commutating Dv/Dt Snubbed for Power Factor = .5 .5 .5 .5 .5 .5

I2t Rating (8.3 ms) [A2S] 1350 1350 7200 15000 20000 1350

General Characteristics

Dielectric Strength (Input-Output-Base) [VRMS] 4000 4000 4000 4000 4000 4000

Capacitance Input to Output [pf] 3 3 3 3 3 3

Ambient Temperature Range (Operating) [ºC] 0 to 40ºC (up to 80ºC with derating)

SCR TechnologyAlternistor

(Inv. Parallel SCRs)Inv. Parallel SCRs

Approval UL Recognize (E175459), CSA, meets EN 60947-4-3 (25/40A meets EN55011)

Mechanical Data

Wire SizeInput Terminals [AWG] 24-10 24-10

[in-lbs] 7-9 7-9Output Terminals [AWG] 8-3 24-10

[in-lbs] 40 7-9

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Wiring DiagramsSeries SAS(R) Solid State Relays

Wiring Diagrams

All SAS3/6 with DC inputSAR6-25-1DSAR6-40-1D

DC Input

All SAS3/6 with AC inputSAR6-25-1SAR6-40-1

I shuntV limit

AC Input

SAR6-50-1DSAR6-75-1DSAR6-100-1D

DC Input

I shuntV limit

AC Input

SAR6-50-1SAR6-75-1

SAR6-100-1

delta starwye

T3T2T1 T3T2T1 T3T2T1

–+

SAR6-30-3(D)

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SAS6(3) Panel Mount Relays

.53(13.5)1.00

(25.4)

6 - 32Thread

Case temp.referencepoint

1.70(43.2)

2.25(57.1)

.30(7.6)

1.10(27.9)

8 - 32Thread

1.75(44.5)

.19 (4.8)

1.875(47.6)

.172 (4.4) Dia. 2 places

.90(22.9)

1 2

3 +4 -

DIN-Rail Mount 1 pole 25/40 Amp

Front View25 Amp

Front View40 Amp

Side View25/40 Amp

DimensionsSeries SAS(R) Solid State Relays

Dimensions are in millimeters (inches). Dimensions not intended for manufacturing purposes.

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DIN-Rail Mount 1 Pole 50/75/100 Amp

50 Amp 75 Amp 100 Amp

DIN-Rail Mount 3 Pole 25 Amp



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SAS


SAS Heatsinks

Part Number: SAS-HTSK-1.0(for most 35-60 amp applications)

1.0 C/W capability


1.6 C/W capability


1.2 C/W capability

Thermal Pad (SAS-THERMPAD5)


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Solid State RelaysSeries SAS(R) Solid State Relays

Notes

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Notes

solid state relays - sprecher + schuh · a solid state relay. units should not be mounted in an...

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