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Unit 1 - 6115 4 St SE
Calgary AB  T2H 2H9


Unit 1 - 6115 4 St SE
Calgary AB  T2H 2H9
+1 403 282-7335

DC Solid State Relay - 30V 100A

ID: 3952_0

This SSR switches up to 30VDC/100amp and connects to a PhidgetInterfaceKit 0/16/16 or OUT1100.


Quantity Available: 353

Qty Price
5 $28.80
10 $27.60

The 3952 DC Solid State Relay can be used to switch loads of up to 100A at 30VDC using a 5V digital output. The Relay comes with an optional protective cover to protect people from touching the exposed high power wires, and a diode to protect your SSR from harmful transients. All wires connect to this relay by screw terminals. If you are switching a high power load or find the relay is getting hot, please consider a heat sink.


  • Capable of switching up to 100 amps of DC current
  • Control power for a circuit or device up to a maximum of 30V
  • Controlled by Phidgets with 5V digital outputs
  • Comes with a diode, relay cover, and thermal pad


This solid state relay can be controlled with Phidget digital outputs. For more details, see the Connection & Compatibility tab.


  1. When choosing a SSR, check the actual load current and the working ambient temperature. Refer to the characteristic curve in the Data Sheet and select the proper heat sink if required.
  2. Use the heat transfer pad between the SSR and the heat sink. Failure to do so can cause overheating and could damage the relay.
  3. Make sure that the SSR terminal screws are tight. If the screws are not tight, the SSR will get damaged by heat generated when the power is ON. Check the Data Sheet for recommended tightened torque.
  4. When an SSR fails, it most often fails permanently closed - leaving your load powered, and possibly creating a fire or safety hazard.
  5. You can use a fuse to protect your circuit from wiring mistakes and accidental short-circuits.
  6. Make sure that you use the relay within the product specifications.


Digital Output Boards

This SSR can be controlled either by using a high-power digital output (such as those on the OUT1100 - 4x Digital Output Phidget) or by using an open-collector digital output and a 5V source, which can be done with the 1012 - PhidgetInterfaceKit 0/16/16.

Product Board Properties
Part Number Price Controlled By
4x Digital Output Phidget
$15.00 VINT
PhidgetInterfaceKit 0/16/16
$95.00 USB (Mini-USB)


If you're switching high current devices or circuits, we recommend that you use a heatsink. In some applications, you may be able to mount the relay to a metal surface which can act as a heatsink by itself. This relay comes with a heat transfer pad that you can sandwich between the relay and the heatsink or mounting surface. When screwed on tight, it will eliminate any air gaps and ensure that the heat conducts from the relay to the heatsink. In cases where the heatsink cannot dissipate heat fast enough, you should add a fan to one end of the heatsink so that air is constantly moving through the fins.

Product Heatsink
Part Number Price Thermal Resistance
Large Heatsink for SSR
Small Heatsink for SSR
$5.50 2.4 K/W

Product Specifications

Electrical Properties
Relay Output Type MOSFET
Isolation Method Photoelectric
Dielectric Strength 2.5 kV AC
Control Voltage Min 4 V DC
Control Voltage Max 32 V DC
Load Voltage Max (DC) 30 V DC
Load Current Min 20 mA
Load Current Max (DC) 100 A
Load Surge Current 240 A
Turn-on Time Max 1 ms
Turn-off Time Max 0.5 ms
Physical Properties
Length 58 mm
Width 45 mm
Height 25 mm
Operating Temperature Min -30 °C
Operating Temperature Max 80 °C
Other Properties
Manufacturer Part Number KS33/D-30D100-L
Customs Information
Canadian HS Export Code 8536.41.00
American HTS Import Code 8536.41.00.50
Country of Origin CN (China)


Here's a list of our DC solid state relays:

Product Electrical Properties
Part Number Price Control Voltage Min Control Voltage Max Load Voltage Min (DC) Load Voltage Max (DC)
DC Solid State Relay - 120V 75A
$45.00 3 V DC 32 V DC 5 V DC 120 V DC
DC Solid State Relay - 30V 100A
$30.00 4 V DC 32 V DC 30 V DC
DC Solid State Relay - 30V 50A
$20.00 4 V DC 32 V DC 30 V DC
DC Solid State Relay - 50V 80A
$25.00 4 V DC 32 V DC 50 V DC