Test Relays

[georgebarr]

I bought some solid state relays on ebay and need to test them since I can send them back if defective. They are Crydom D2440 Solid State Relays. It has DC inputs and AC outputs. Turn-on voltage is 3.5 vdc and turn-off voltage is 1.vdc. What does the turn-on and turn-off mean? How can I test these things?

[wjbzone]

If you supply 5v (or voltage above 3.5) to the the DC side it turns on the AC side. When 0 volts (or less then 1v) to the DC side turns off the AC side.

Note that when the 5v is applied on the DC side you will not be able to measure continuity across the AC side, but when you apply the rated voltage across the AC side it will flow.

Bill

[owhite]

Piece of cake.

This mouser catalog page has a little information:

http://www.mouser.com/catalog/617/918.pdf

Which from reading I assume that your relay will turn-on when voltage between 3-32volts is placed on the DC input. Turn-on voltage refers to the threshold input the relay has to see in order to conduct electricity through the AC outputs. Turn-off voltage is probably how low the voltage has to drop to shut off the relay.

To test: Apply some voltage above 3 volts to the input of the relay, say with two small D or C cell batteries, and you should see continuity on the AC output. If it works you should have no problem with running AC current through the relay and use it as a switch.

Owen

[owhite]

Heh, looks like Bill was composing his message while I was writing mine -- sorry for the redundancy.

O

[georgebarr]

This is how I am testing 6 of these relays. I am using a DC adapter which outputs 12VDC. I applied this 12VDC to the OUTPUT (AC) of the relays and applied no voltage to the input (DC side) of the relays. Even though I am suppose to apply AC voltage to the output side instead of 12VDC, this test should result in no voltage going through. When attached in series to a multimeter, it shows 12VDC going out when no voltage should be going out.

[georgebarr]

I just tested these relays using a 120 VAC applied to the relay output in series with a multimeter to measure the AC voltage. I first used to voltage in the input to the relay and then again using 12VDC as the input. In all cases, the multimeter shows 120VAC at the output. These are used relays I bought at ebay. Should I return them?

Thanks,

[wjbzone]

I though I had a problem with mine when I tested them with a volt/ohm meter. (ie I could read voltage across the 120AC side with no dc voltage to switch it on)

When I hooked the AC side up to something that draws some current (try a light bulb), it will work.

Bill.

[Al_The_Man]

Bill, Using a high impedance meter like the modern VOM's are can give misleading reading when using the meter on solid state devices that have no load on them, There is enough conduction through most scr/triac devices to register voltage on very sensative meters, if measuring voltage output its best to put a load on them.
Al

[pack rat]

I found that those relys are very reliable.You can test two at time. Take the lamp and cut two wires, now you have four ends. Connect each end to each 120V terminal on rely. Connect DC in parallel to control (DC terminal), if lamp lights up relays are good.

[yukonho]

Do you want to sell one of the relays?
co

[georgebarr]

I retested my relays using a lamp with a light bulb. The results were that all the relays worked perfectly. Someone mentioned that you must test these relays using some sort of load like a light bulb. Thanks to everyone for your help.