Solid State Relay (SSR) not shutting off

[KartRacer54]

Installed my Crydoms and fired up the HLT at 168 degrees. The Crydoms do not have led but the temps overshot. Using a VM I determined the pid ( Mypin ) continued to provide 24v to the SSR.
Any suggestions other than dumping the MyPin and move up to Aubern.
So many people have used the lessor expensive units with success. What is my deal. Such a waste of funds.
HELP!

 

[JONNYROTTEN]

I cant help with the problem but I can say I use a Crydom with a Mypin with no issue. I actually went the other way. I started with an Aubins and it crapped out after a year and Aubrins basically said too bad so I bought a Mypin and its been working fine...I don't feel there is anything whatsoever that makes Aubrins better than Mypin. They also don't stand behind there product

 

[augiedoggy]

Installed my Crydoms and fired up the HLT at 168 degrees. The Crydoms do not have led but the temps overshot. Using a VM I determined the pid ( Mypin ) continued to provide 24v to the SSR.
Any suggestions other than dumping the MyPin and move up to Aubern.
So many people have used the lessor expensive units with success. What is my deal. Such a waste of funds.
HELP!

Have you tuned the mypin? If they are not calibrated correctly for the application any PID will overshoot regardless of brand or cost . You can't just use the default settings and expect them to climb and maintain temps without overshooting. And even if you do preform the autotune you have to make sure the conditions are the same as the would be during brewing such as volume, flow rate and even the grain if your trying to maintain mash temps because of the time delays involved.

 

[JONNYROTTEN]

^^^ This is probably the reason many people have a problem with autotune....To many variables. I don't trust it anymore. I'd rather be confident my brew will only drop 5 deg (mostly at the end) then be higher by 10 or more with autotune the whole time...killing the power to the element assures no overshoot

 

[augiedoggy]

^^^ This is probably the reason many people have a problem with autotune....To many variables. I don't trust it anymore. I'd rather be confident my brew will only drop 5 deg (mostly at the end) then be higher by 10 or more with autotune the whole time...killing the power to the element assures no overshoot

There really shouldn't be too many variables if your always using it for the same thing in the same way? I never have an issue. I brew both 6 and 11 gallons at a time no adjustments needed since I calibrated from rims flow.

 

[KartRacer54]

So

Have you tuned the mypin? If they are not calibrated correctly for the application any PID will overshoot regardless of brand or cost . You can't just use the default settings and expect them to climb and maintain temps without overshooting. And even if you do preform the autotune you have to make sure the conditions are the same as the would be during brewing such as volume, flow rate and even the grain if your trying to maintain mash temps because of the time delays involved.

ry should have been clearer, not overshoot but runaway!

 

[KartRacer54]

Well I fired up the panel and set HLT pid to 150 and redid the auto tune. Pid and ssr ran as it should.
Pumped water to mash tun and ran through the rims at 153 again redoing the auto tune. Both functioned normally.
I'm guessing that after installing new ssr resetting auto tune was necessary. Thanks for everyone's input. Have fingers crossed that everything will operate as expected next round.

 

[augiedoggy]

SSR has nothing to do with PID tuning.. not sure what was wrong.

 

[KartRacer54]

SSR has nothing to do with PID tuning.. not sure what was wrong.

Well I didn't think so but I'm still learning this system.

 

[augiedoggy]

Well I didn't think so but I'm still learning this system.

That's why I posted as such. Just to let you know if you weren't sure.

 

[processhead]

Deleted

 

[nitrografix]

Use a regular contactor, Siemens, Eaton, they all work well and you know when they are faulty when they’re not pulled in

 

[doug293cz]

Use a regular contactor, Siemens, Eaton, they all work well and you know when they are faulty when they’re not pulled in

Contactors are suitable for turning power on and off at low duty cycles, and are advantageously used for positive power disconnects within brew control panels. However, the PID duty cycle for pulse width modulation (PWM) of power to the heating elements in most homebrew systems is 1 - 2 seconds. That means that unless you are at 100% power, the PID will be switching power on and off 60 - 120 times per minute. Contactors are not designed for switching at this rate, and will be very noisy to boot. And, if you are using Auber EZBoils instead of ordinary PID's, your switching cycle time is 16.7 ms, and requires switch transition times of micro seconds. Contactors won't handle this at all.

So, PID's or EZBoils should be used to drive SSR's for element power modulation. Save the contactors for main power control and element power enable disconnects.

Brew on