BCS system, Seven Segment and Element problems

[Bsquared]

Yesterday was the first brew day on my new system, this will be the third panel I have built and was really happy with the way it came together this time.

I added a few more bells and whistles this time though, and have run into a little bit of a issue that has me scratching my head.

First issue is with the Seven seven segment displays, They work fine but when the system is powered on but when I energize the contractor to select witch element is going to get power (the HLT or BK) the displays turn on and off and reset. Also when brewing and the pumps and elements are on The BCS becomes some that unresponsive if the displays are active. If I turn the displays off the BCS communicates quickly.

I'm thinking this might be due to the 12v DC power supply that powers the displays being on the same neutral bus as the 120VAC coils. I have the BCS and the 12v DC power on a separate 120VAC leg than what is powering the coils, But do I now have to set up an independent neutral bus for that leg too?

The second issue was with the 220VAC kettle element plug, I have this set up that one leg of the element is controlled by a 40A SSR and the second leg is controlled by the 2 pole contractor that both legs run through to get to the outlet. I have a pilot light that branches off the outlet, so therefor It should only be lit when the outlet is energized.

When I was brewing,and was firing the BK element the pilot light was on and the Element was heating but very slowly. I set the BCS to run it 100% but it still seemed to be putting out about 1/2-3/4 power. When i plugged the element in to the HLT outlet (that Is wired the same way) The element worked as I expected and was able to give me a robust boil, where the best I was able to get before was a simmer/light boil.

I checked the DC power controlling the SSR from the BCS and that was 5v, and because the pilot light was on there must have been 220vac power at the outlet. The light was pulsing erratically which leads me to think its the SSR, but I thought when SSR's failed they failed closed, so I should be getting 100% power if that happened and not intermittent power.

Any one have any good Ideas about what to test? I'm probably going to swap out the SSR, and see where that leads me first. Then check my power connections to make sure every thing is tight.

 

[Bsquared]

Crickets eh?

Thinking a 12V DC relay for the elements might do the trick. with the displays.

still need to swap out the ssrs running the element.

 

[BrunDog]

Your AC ground, and all DC grounds should be tied together in a star configuration. Use a voltmeter to see what happens to the display feed power.

Sounds like the SSR is bad. Put a voltmeter across the element when it is ON. Don't use PID to test - use the digital output button. Should be near 240 (will be slightly less than the incoming due to wiring voltage drop). Or replace it and find out.

Without a schematic it would be difficult to propose much more.

 

[crane]

I had similar issues with my 7 segment displays resetting when I first built my BCS panel. Flipping switches on the panel for the element contactors caused them to reset. This was because I had ran the wires for the displays too close to the 120V wires for the contactors and they were picking up EMI from the 120V wires. I separated the display wires from any 120V wires as much as I could and the problem has gone away.

As for separating the neutral busses, you can't do it effectively. Ultimately all neutrals are tied together and tied to ground in your breaker box. Even if you separate them they will connect to the same neutral feed coming into to control panel.

Now for the boil kettle element. I would (very frickin carefully) measure the voltage across the 2 hots starting from the element plug in the panel back to SSR and contactor to see why you aren't getting full power. Could be a loose connection somewhere. I've seen you have had problems with this in the past on this forum.

I too am in San Diego and would be willing to come take a look at your panel if you want any help.

 

[Bsquared]

Thanks for the input, I definitely think Brun Dog is on to it with regards to the 7-segement displays. I set up a ground bus, and did not use a star pattern.

As for the element, Im suspecting the SSR is the problem, but will check all the connections to. With this build I used a ratcheting crimper and lots of terminal blocks. Im fairly confident the the connections are tight, but I might have missed some thing, will check it out this weekend.

Also a good thing to look into is how isolated the cables connecting the displays are to the coil switches, I bet that might be contributing to the problem.

Thanks
B^2

 

[Bsquared]

Little update, I have swapped out the SSR, now the boil kettle element is functioning properly. I also rewired the grounding in a star pattern, but that has not resolved the 7 segment display issue. Because it really only happens when the contractors are being engaged, I think Im going to swap them out with different contactors. Though rewiring the grounding has seemed to make the BCS a little more stable, but I have not run a full brew cycle on it yet, just short test runs, but the communication seems to be improved.

 

[sandyeggoxj]

Do you have an illustration of the star pattern?

 

[Bsquared]

Late reply but...The star pattern is basically terminating all the grounding lines to one point. I have to tell you this was a challenge with my set up!

For the most part I have the system up and running. After a lot of testing and swapping out relays. what I eventually figured out was the SSR were wired up wrong. Though this did not effect each leg running independently, i.e. 220VAC elements or 120VAC motors, when the motors and elements where run together every thing shut down. After wiring all the ssr's with the load coming into the #1 post and #2 out to the motors and element's are working fine together...except the 7 segment displays are still having issues.

My plan is to do a wet run this weekend and confirm every thing is functional, and then swap out the DC power supply for the displays and see if that corrects their issue.