Relay to switch on a valve that needs 12VDC, 20W

Electromechanical Relays
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1

I need a relay, normally open, that would pass 12 VDC through when actuated with 5V DC.
I purchased CC1060-ND. It works as long as there is no load, but the output voltage drops down to zero when the load is connected. I’m guessing it is because the max load current for this part is 1 A. My load is a solenoid valve which needs ~1.6 A.

I wonder if there is a similar part with a higher max current rating, at least 2 A?

Any advice would be much appreciated.

Additional information: My control signal is generated by NI’s myDAQ, which is USB-powered.

2

The CC1063-ND was found.
It would be a 5A option
CX240D5 Sensata-Crydom | Relays | DigiKey

The below link shows all options I had found that would work and would be able to handle the 1.6A.
SPST-NO (1 Form A) 4-SIP Solid State Relays | Electronic Components Distributor DigiKey

3

Thanks, Nathan for a prompt response.
According to the spec sheet [CX240D5 Sensata-Crydom] is built for AC Voltage output. I wonder if it would work for DC output. Please let me know.

4

No. Such relays use thyristor output devices, and depend on zero crossings of the AC waveform for commutation.

One of these would be a better selection based on the information given.

5

Hi Rick,
Thanks for your help. Seems like CPC1706Y would serve my purpose. The required input voltage is specified as 1.2 VDC, but no range is given. I wonder if you know the lowest and highest voltages needed to turn it on. Thanks

6

The input is the LED side of an optocoupler, and should be driven like any other LED.

Detailed specs for the device are in the datasheet, but the long & short of it is that to turn the thing on, you need to ensure that a current between 5 and 50 mA goes through the input in the proper direction.

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7

Hi anaqwi,

If you prefer a relay that doesn’t require current limiting on your input signal (adding an in-line series resistor of the appropriate value), these are a subset of Rick’s previous list which will take 5V directly.

You’ll notice a significant premium charge for the privilege of not having to add current limiting separately.

8

The Forward Voltage Drop on the internal LED is around 1.36V typical.

You can give that LED any voltage greater than 1.36VDC as long as you keep the current between around 10mA and 40mA.

Lets say you’re giving it 5VDC.

To calculate your current limiting resistor you subtract the Forward Voltage Drop from your Source voltage of 5V.

5V - 1.36V = 3.64VDC

That’s the voltage that is going to be across the current limiting resistor.

To do Ohms Law to calculate what resistor you need, let’s give it say, 10mA.

3.64VDC/0.01A = 364 Ohms.

Here is a 365 Ohm 1% 1/4W resistor

RNF14FTD365R Stackpole Electronics Inc | Resistors | DigiKey

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9

Thanks, David and Kristoff,
This is very helpful and educational for me because I’m not an EE by training. I just have to decide between the options now.
Best
Amir

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