SSR Troubleshooting Help

Put together my 240v controller based on P-J's design for single PID / single element. Using Auber 2352 PID, contactor, and ebay SSR first now Crydom 2440 SSR.

Got everything together and all the physical switches work but the PID doesn't appear to be cycling the heating element based on the temperature readings. The first SSR I had was a cheapo ebay one which I assumed was fried. So I bought a Crydom 2440.

Got everything hooked up but the PID still isn't cycling the element. When I put my voltmeter on the posts, both post 3 & 4 have 120V on them, even though posts 1 & 2 (control) only have 1-1.5v so shouldn't be switching the SSR on. Is this crydom one fried too or am I missing something?? Only thing I see is that the SSR is specd for 240V 40A, would it matter that I'm only using 120V on it (does it have to be 240v)?

Thanks for any help.

SSR output should measure 12VDC on pins 7 and 8 when the PID is trying to turn the SSR ON.

I think these Auberins PIDs need a valid temp sensor input to function, is the RTD hooked up and PID programmed for the correct temp sensor?

Use manual mode and set the PID to 100% power and check the PID output, input control voltage at the SSR, and voltage output from the SSR.

The temp sensor is hooked up, not sure what setting is configured in the PID but it's displaying what seems to be the correct temperature (using K type sensor). I will check out the voltages with the scenario you suggested later today.

if using a k-type thermo couple, these are the auber instructions

The thermocouple should be connected to terminals 4 and 5. Make sure that
the polarity is correct. There are two commonly used color codes for the K
type thermocouple. US color code uses yellow (positive) and red (negative).
Imported DIN color code uses red (positive) and green/blue (negative). The
temperature reading will decrease as temperature increases if the connection
is reversed

and for a k-type thermocouple, make sure SN is set to 0

Sn code Input device Display range (ºC) Display range (ºF)
0 K (thermocouple) -50~+1300 -58~2372

as for the SSR, check what the input signal is rated at. the 2352 should output 12 vDC and that SSR (i think) will wake 3-32 vDC as its signal.

as icos said, check what the pid is actually putting out.

With the K-Type, did you use the specific K-Type wiring for any extensions you did, or any runs from a quick connect to the PID? A lot of people have been having problems with the K-Type probe because they have very specific requirements for the wiring used. You can get some screwy results if you mix it up.

Otherwise, follow the advice from the rest of the posts, and check everything starting from the most up-stream device on down. Also - do you have your element plugged in? I was having issues with my SSR not opening / closing properly, but it was because I had no load on the system. Plug in your element if you haven't already and see if it works.

-Kevin

yes I'm using a quick disconnect for the temp probe, and I'm using specific K-type wiring on both sides. The PID does read the temperature that appears correct (I haven't verified with a thermometer but reads ~70 degrees for room temperature water seems about accurate. Also the heating element does work the problem is that it doesn't cycle off, i.e. 100% on all the time regardless of PID target temperature. I will do some more testing when I get home this afternoon and report back. Thanks for all the tips.

Do you have heating element hooked up? I just finished my control panel on Monday and noticed the same behavior. I panicked until discovering "SSR leakage" and realized that is the phenomenon I was experiencing. Since ssr has no moving parts, output voltage will match input voltage with no load, even though no real power is being transmitted. This is enough to light an indicator led or measure on a dmm until element is connected.

Also, since search function stinks, you may have better luck google searching for "SSR leakage homebrewtalk".. I have found this to be much more helpful for all my searching needs.. Good luck, apologies if I am off base on the problem you are experiencing.

bambari said:

Do you have heating element hooked up? I just finished my control panel on Monday and noticed the same behavior. I panicked until discovering "SSR leakage" and realized that is the phenomenon I was experiencing. Since ssr has no moving parts, output voltage will match input voltage with no load, even though no real power is being transmitted. This is enough to light an indicator led or measure on a dmm until element is connected.

Also, since search function stinks, you may have better luck google searching for "SSR leakage homebrewtalk".. I have found this to be much more helpful for all my searching needs.. Good luck, apologies if I am off base on the problem you are experiencing.

Click to expand...

Or better yet: site:homebrewtalk.com "SSR leakage"

pidass said:

yes I'm using a quick disconnect for the temp probe, and I'm using specific K-type wiring on both sides.

Click to expand...

Good - we can eliminate that potential headache.

bambari said:

Do you have heating element hooked up? I just finished my control panel on Monday and noticed the same behavior. I panicked until discovering "SSR leakage" and realized that is the phenomenon I was experiencing. Since ssr has no moving parts, output voltage will match input voltage with no load, even though no real power is being transmitted. This is enough to light an indicator led or measure on a dmm until element is connected.

Click to expand...

This (wo)man speaks the truth. I had a similar issue / freak out. Wired the whole panel, checked everything twice, and was getting all kinds of crazy voltage / SSR leakage / LEDs illuminated when they shouldn't be. Plugged in the element - problem solved.

-Kevin

I checked out the PID its working as it should, the SSR output is pushing 12 VDC when it's supposed to correctly. However, with the SSR having 120v on one of the output ports it always has same voltage on the other output port, regardless of control voltage. I even tried disconnecting the control ports entirely and the SSR still passes through voltage so it appears to be stuck closed.

What you haven't answered though is if you have any load on the SSR - IE, do you have your element plugged in? I had the EXACT same issue you're having, until I plugged my element into the outlet that the SSR controls. The resistance from the element is enough to cause the SSR to open / not leak voltage. If you haven't tried it with the element plugged in (and submerged - don't dry fire it... at least not for any appreciable amount of time), please do so.

If you have, and your SSR is still performing as described, then I'd agree that it's bad.

pidass said:

I checked out the PID its working as it should, the SSR output is pushing 12 VDC when it's supposed to correctly. However, with the SSR having 120v on one of the output ports it always has same voltage on the other output port, regardless of control voltage. I even tried disconnecting the control ports entirely and the SSR still passes through voltage so it appears to be stuck closed.

Click to expand...

Please do yourself a service and research "SSR leakage". The conditions you are describing are the exact same that BadNews and I are trying to explain. An SSR will "leak" a nominal amount of current regardless of input control circuit conditions. Once you add a load, it will pull the SSR open circuit down. Do not expect to stick a multimeter on an open SSR and expect to see 0V.

@ BadNews 28/m/Indy

SSR's control current, not voltage, so if there is no load, you'll see some residual voltage on the output - they can easily leak a few milliamps which will light up the common LED indicators and show lots of voltage with multi-meters.

Until you connect a load that's designed to pull lots of power, you can't make any assessments on whether a SSR is working.

I have discconects for all my elements, and whenever i turn my control panel on without them connected, all the "element on" lights glow. as soon as i connect the elements they shut off.

put load on the ssr, no change, the SSR always leaked regardless of voltage on the control side. Sending the SSR back to get a new one. Guess I won't be brewing this weekend

pidass said:

put load on the ssr, no change, the SSR always leaked regardless of voltage on the control side. Sending the SSR back to get a new one. Guess I won't be brewing this weekend

Click to expand...

Sorry to hear it. While you certainly could have had two bad SSRs, are you sure that there isn't something else going on? That would be more likely than two bad SSRs, but again, it is possible.

The first one was doing something different, it seemed to be leaking voltage from the output side to the control side, i.e. I was seeing AC 120V on the control + post, it was a cheapo chinese thing so I wasn't really surprised but expected more from the Crydom. Either way the ebay seller agreed to send me another one, just sucks I have to wait....was going to do my first all-grain BIAB while my amber ale is bottle conditioning.