Exploded SSR / Loud Pop / PLEASE HELP

[brandonring]

Ok so I'm pretty shaken up. I knew I was no electrician going into this but I thought I had it wired correctly. I'm fine. Did not receive any shock.

I'm building a very simple electric HLT. I must have wired something wrong b/c when I flipped the switch on my project box, my box jumped from the table and the SSR inside was fried. The 30 amp breaker in the main panel had tripped but the 50 amp GFCI had not. Feel free to tear me a new one. I'm ashamed of myself and pretty flustered.

Here's my wiring diagram

Here's my list of materials.
http://www.lowes.com/pd_591488-427-3032WZ_0__?productId=50179201#img

http://www.amazon.com/gp/product/B0087O6T10/?tag=skimlinks_replacement-20

http://www.lowes.com/pd_423568-43469-2203___?productId=4013827&pl=1&Ntt=30+amp+dryer+outlet

 

[NoIguanaForZ]

My sympathies on your brand new Gaseous State Relay.

It's not obvious to me what's wrong here, assuming this was wired per the chart. Was the PID fuse blown?

 

[brandonring]

No the PID fuse was fine. I'm thinking the switch may be an area of concern. Says 30 amp 120v - 270v on the switch. Lowes had it rated for 120v in the description online. The SSR probably should have been grounded but I don't think that would be the cause. I had it wired exactly as pictured. I'm pretty concerned that the gfci wasn't tripped.

 

[NoIguanaForZ]

...wait.

Is that gray thing to the left of the SSR your breaker?

If so, I think the only way to get the specific pattern of failures you describe is either to MASSIVELY exceed the SSR's current rating (which I can't read from here, but which seems unlikely with all those fins) or to have shorted the red and black AC wires together on the far side of the SSR: most likely either a short in the plug itself (was anything plugged into it?) or, most likely if the gray thing is your breaker, by accidentally wiring the red and black AC wires to opposite sides of the same pole instead of to separate poles (this looks like the culprit given how you've drawn the wiring, based on the arrangement of terminals on literally every breaker I can remember encountering).

[EDIT] sounds like the gray thing is the switch. Same potential problem, though the terminal arrangement is less obviously problematic.

 

[Bobby_M]

The way you have that switch wired, the L1 hot shorts directly to the L2 hot. The poles of the switch run vertically not left to right.

 

[brandonring]

It's worth mentioning that everything was fine and I had even tinkered with the PID settings before I flipped the switch. I didn't have the element plugged in at the time.

 

[brandonring]

The way you have that switch wired, the L1 hot shorts directly to the L2 hot. The poles of the switch run vertically not left to right.

Thank you guys! Are all switches that way? I don't know why I assumed left to right was correct. If I replace the switch and SSR does everything else seem ok? I've scared myself now.

I'm correct in wiring a ground instead of a neutral to the 3rd prong of the far left outlet? Should I ground the SSR/heatsink at the mounting point?

 

[stevehaun]

Yes, most switches are that way. Hopefully you did not fry your PID. If you replace the switch and SSR, you should be good if you wire it correctly.

Make sure you get a switch rated for 30 amps, 240 vac:
https://www.menards.com/main/electr...4451204960-c-6324.htm?tid=9199831603642715682

Or better yet, use a contactor:
http://www.ebay.com/itm/Packard-C24...hash=item23521d1c0d:m:mUujhlrm_eZ_UQ5ZYaviuMg

 

[doug293cz]

Is the switch a double pole switch (pic looks like a single pole, but may not actually be representative)? If not, there is no way it will work in the circuit. You need something like a Leviton 3032 series switch. Then make sure the switch is wired correctly, as Bobby noted.

Brew on

 

[caseyw]

Ok. Folks - this is why you get someone who knows what they are doing to help you out on stuff like this. I joined this forum just to reply to this post.

What this poor fellow has done is downright dangerous - and he is lucky to be alive.

A couple of notes here to start off:

The light switch you are using is designed for 115VAC @ 15A MAX. This is way underrated for your application.

The SSR you have should be in series with one of the legs of the AC power, connected to one of the ends of your heater element.

Your temperature controller must have some means of measuring the temperature! This is not shown in your diagram!

Your heating element is not shown in your diagram!

Make sure you have configured your temperature controller for pulse output!

If you look at the attached PDF - this is a suggestion for how one of these circuits MIGHT BE CREATED. I do not recommend you attempt to construct a circuit like this without the assistance of a qualified professional! I make no claim on the validity of this schematic.

As an aside - what he has is not called a "PID" it is a temperature controller. PID stands for Proportional, Integral, Differential, and is a closed loop feedback control algorithm that is employed by the temperature controller to apply the correct amount of power to his heating element.

View attachment Drawing1.pdf

 

[jsbird]

Couldn't agree more with the last post. Original poster is lucky to be alive as that circuit is a death trap; 240 volts going through an completely unsuitable switch that he was directly touching. Please chuck everything attached to this setup and start over with some professional guidance.

 

[doug293cz]

Ok. Folks - this is why you get someone who knows what they are doing to help you out on stuff like this. I joined this forum just to reply to this post.

What this poor fellow has done is downright dangerous - and he is lucky to be alive.

A couple of notes here to start off:

The light switch you are using is designed for 115VAC @ 15A MAX. This is way underrated for your application.

No, the switch OP is using is a Hubbell 3032W, which is rated for 30A @ 277VAC (ref: http://ecatalog.hubbell-wiring.com/productinformation/specsheets/3A/Live/PDF/HBL3032W_cart.pdf.) It is double pole, single throw, and is rated adequately for the intended use.

The SSR you have should be in series with one of the legs of the AC power, connected to one of the ends of your heater element.

The SSR is wired in series correctly. The drawing uses an incorrect line color, but the topology is correct (up to the switch.)

Your temperature controller must have some means of measuring the temperature! This is not shown in your diagram!

Correct. Hopefully OP has it connected and just left it out of the drawing. The PID won't function correctly without a temp probe connected.

Your heating element is not shown in your diagram!

Outlet for the heating element is in the upper left corner, just to the right of the power feed.

Make sure you have configured your temperature controller for pulse output!

The MyPin TD4-SNR only has pulse output mode. It is specifically intended for use only with SSR's.

As an aside - what he has is not called a "PID" it is a temperature controller. PID stands for Proportional, Integral, Differential, and is a closed loop feedback control algorithm that is employed by the temperature controller to apply the correct amount of power to his heating element.

The MyPin TD4-SNR is a PID controller (ref: http://blog.uvm.edu/cwcallah/files/2016/04/AGPTek-PID-Controller-PC17-user-manual.pdf.)

The biggest mistake the OP made was wiring the switch incorrectly. Another major mistake was not testing out connectivity (in both switch positions) before applying power to the circuit. Trying something like this without a complete understanding of the circuit, and not getting qualified help to review the design and build, represents a lapse in judgment.

Brew on

 

[Bobby_M]

Many people incorrectly jump to the conclusion that those kinds of toggle switches can't possibly be rated for 30 amps. Following the link would have solved that.

 

[idiotsinc]

Yes, most switches are that way. Hopefully you did not fry your PID. If you replace the switch and SSR, you should be good if you wire it correctly.

Or better yet, use a contactor:
http://www.ebay.com/itm/Packard-C24...hash=item23521d1c0d:m:mUujhlrm_eZ_UQ5ZYaviuMg

Use a contactor. And put it at the beginning of your circuit as it comes into your box, not before the outlet. Then you have more options to shut off the 240v before it fries your controllers. There's a lot of info on this site on accomplishing this but you might be better off bribing a friendly electrician with some homebrew down the line.

 

[doug293cz]

Use a contactor. And put it at the beginning of your circuit as it comes into your box, not before the outlet. Then you have more options to shut off the 240v before it fries your controllers. There's a lot of info on this site on accomplishing this but you might be better off bribing a friendly electrician with some homebrew down the line.

A contactor wouldn't solve the problem of incorrect wiring. The switch used would have been fine if wired correctly.

Brew on

 

[passedpawn]

Thought I'd point out to the OP that the GFCI didn't trip since there was no loss of current to ground. That's when they trip. There was a short between L1 and L2 apparently, which would trip the breaker but not the GFCI.

 

[brandonring]

Is the switch a double pole switch (pic looks like a single pole, but may not actually be representative)? If not, there is no way it will work in the circuit. You need something like a Leviton 3032 series switch. Then make sure the switch is wired correctly, as Bobby noted.

Brew on

Double Pole Single Throw 30 Amp

The problem was the order i had the wires on the switch......

 

[brandonring]

Thought I'd point out to the OP that the GFCI didn't trip since there was no loss of current to ground. That's when they trip. There was a short between L1 and L2 apparently, which would trip the breaker but not the GFCI.

Thanks. Good to know it's not faulty.

 

[brandonring]

No, the switch OP is using is a Hubbell 3032W, which is rated for 30A @ 277VAC (ref: http://ecatalog.hubbell-wiring.com/productinformation/specsheets/3A/Live/PDF/HBL3032W_cart.pdf.) It is double pole, single throw, and is rated adequately for the intended use.

The SSR is wired in series correctly. The drawing uses an incorrect line color, but the topology is correct (up to the switch.)

Correct. Hopefully OP has it connected and just left it out of the drawing. The PID won't function correctly without a temp probe connected.

Outlet for the heating element is in the upper left corner, just to the right of the power feed.

The MyPin TD4-SNR only has pulse output mode. It is specifically intended for use only with SSR's.

The MyPin TD4-SNR is a PID controller (ref: http://blog.uvm.edu/cwcallah/files/2016/04/AGPTek-PID-Controller-PC17-user-manual.pdf.)

The biggest mistake the OP made was wiring the switch incorrectly. Another major mistake was not testing out connectivity (in both switch positions) before applying power to the circuit. Trying something like this without a complete understanding of the circuit, and not getting qualified help to review the design and build, represents a lapse in judgment.

Brew on

VERY informative post. Thanks Man.

 

[brandonring]

Round 2

I realize what I did before was stupid. I at LEAST should have tested the circuits with a multimeter before introducing power. I've made some changes and I'm starting over. I've labeled the amperages this time to be less confusing to those who didn't follow the previous links to my equipment. I've also added an 120v outlet for my pump, 2 rocker switches, and some indicator lights. What do you guys think? I thought i would post in this thread first before cluttering the board with another thread.

P.S.
The RTD temp probe is not in the diagram but is present and would be correctly wired.
The 3 prong outlet is where the element plugs in. (5500w)

Forgive my drawing. It was done in mspaint and got cluttered after i added the additions.

 

[brandonring]

Some specific questions I have:

Am i correct in assuming the alarm output from the PID is 120v AC, and not 12v DC like is sent to the SSR?
Is the other indicator light (for when the element is ON) properly wired? I cant figure out why but something doesn't feel right to me.

I will not power this system until it has been looked over by an electrician. My father in law is an electrician but he is older and isn't familiar with the PID Controller and SSR aspects of the circuit.

 

[Firewalker11]

Casey tied it up in a bow for you. Loose the switch and get a contactor instead. I opted for a keyed switch for the contactor for an extra layer of safety.

Good luck!

 

[caseyw]

No, the switch OP is using is a Hubbell 3032W, which is rated for 30A @ 277VAC (ref: http://ecatalog.hubbell-wiring.com/productinformation/specsheets/3A/Live/PDF/HBL3032W_cart.pdf.) It is double pole, single throw, and is rated adequately for the intended use.

I stand corrected - the data sheet says something different than the website op linked. Thanks for pointing that out!

The MyPin TD4-SNR is a PID controller (ref: http://blog.uvm.edu/cwcallah/files/2016/04/AGPTek-PID-Controller-PC17-user-manual.pdf.)

I realize that his temperature controller uses a PID algorithm, just a pet peeve of mine to call it a "PID"... you see this all the time on the espresso machine forums they actually pronounce it a "pid" and it drives me nuts

By the way, anyone who sees this message and needs help getting something like this wired up and lives in the bay area (california) I would be more than happy to assist.

 

[caseyw]

Many people incorrectly jump to the conclusion that those kinds of toggle switches can't possibly be rated for 30 amps. Following the link would have solved that.

My point was that this is not the correct application for that kind of switch, regardless if it is rated correctly or not (which I did not make very clear, btw) but thank you for pointing that out.

 

[passedpawn]

My point was that this is not the correct application for that kind of switch, regardless if it is rated correctly or not

Maybe you should say why.

I've been using 2 of those types of switches on my 240V 5500W system that I built in 2009. Not a problem. I found a dbl pole (DPST) 30A 240V switch at home depot. Electrical elements are purely resistive and I think are the nicest sort of load you could put on a ckt.

 

[caseyw]

Some specific questions I have:

Am i correct in assuming the alarm output from the PID is 120v AC, and not 12v DC like is sent to the SSR?
Is the other indicator light (for when the element is ON) properly wired? I cant figure out why but something doesn't feel right to me.

I will not power this system until it has been looked over by an electrician. My father in law is an electrician but he is older and isn't familiar with the PID Controller and SSR aspects of the circuit.

Don't assume anything, the alarm output is merely a set of contacts that you would use in an external circuit to take some sort of action if the alarm condition you program in to the controller is reached. Generally speaking you could set up a circuit with a normally closed contact of a pilot relay that drives your contactor, you could set the alarm condition to some temp much higher than you expect to ever get to (run away control algorithm, shorted SSR, etc)

Effectively this could go in series with your switch....

I quickly drew a mock up in single line to give you a suggestion of how it might work (again, this attached pdf is for information only, do not build directly off of the attached drawing)

View attachment Drawing2.pdf

 

[caseyw]

Maybe you should say why.

I've been using 2 of those types of switches on my 240V 5500W system that I built in 2009. Not a problem. I found a dbl pole (DPST) 30A 240V switch at home depot. Electrical elements are purely resistive and I think are the nicest sort of load you could put on a ckt.

Force of habit? Safety? To tell you the truth for me it has mostly to do with my personal acceptable level of risk. If I'm switching power, I want that switching to happen remotely inside of an enclosure. I have built large machines, and it is generally a no-no to switch devices under load, whether that is purely resistive or reactive. If I was to design a system for an electric brewery it would be with a contactor. If you are comfortable using a light switch, and it is working for you, there is no real reason to change it. As I say with anything that I do whether it is in personal or professional life - safety is the #1 priority.

 

[doug293cz]

Round 2

I realize what I did before was stupid. I at LEAST should have tested the circuits with a multimeter before introducing power. I've made some changes and I'm starting over. I've labeled the amperages this time to be less confusing to those who didn't follow the previous links to my equipment. I've also added an 120v outlet for my pump, 2 rocker switches, and some indicator lights. What do you guys think? I thought i would post in this thread first before cluttering the board with another thread.

P.S.
The RTD temp probe is not in the diagram but is present and would be correctly wired.
The 3 prong outlet is where the element plugs in. (5500w)

Forgive my drawing. It was done in mspaint and got cluttered after i added the additions.

Neither of the lights is wired correctly. The alarm light has no power supply, and the element firing light will prevent the element from working.

You don't need to switch the neutral lines going to the PID or pump outlet. So, you could use single pole switches for those functions.

You should move the PID fuse to before the PID switch, and add a 10A fuse before the pump switch.

You don't need 10AWG wire for the PID power connections. After the 1A fuse, you can use as low as 20AWG. Smaller wire is much easier to work with. Likewise after the 10 pump fuse you can use 16AWG wire.

I'll put together a corrected version of the drawing, but won't get it done until tomorrow afternoon at the earliest.

Edit: Missed on first review that the hot line into the SSR cannot go thru a 20A switch, so it needs to be rerouted.

Brew on

 

[The10mmKid]

This illustrates the switch wiring, Fig #2:

http://ecatalog.hubbell-wiring.com/productinformation/CustomerDrawingLibraryAssets/3A/3/PD1242.pdf

That's a heck of a lamp at 30A

 

[brandonring]

Neither of the lights is wired correctly. The alarm light has no power supply, and the element firing light will prevent the element from working.

You don't need to switch the neutral lines going to the PID or pump outlet. So, you could use single pole switches for those functions.

You should move the PID fuse to before the PID switch, and add a 10A fuse before the pump switch.

You don't need 10AWG wire for the PID power connections. After the 1A fuse, you can use as low as 20AWG. Smaller wire is much easier to work with. Likewise after the 10 pump fuse you can use 16AWG wire.

I'll put together a corrected version of the drawing, but won't get it done until tomorrow afternoon at the earliest.

Edit: Missed on first review that the hot line into the SSR cannot go thru a 20A switch, so it needs to be rerouted.

Brew on

First off thanks for being so accommodating. I'm very appreciative.

Since my rocker switches are DPST would you
1. Leave the neutrals switched?
2. Just use 2 pins?
3. Suck it up and buy new switches?

Good eye catching that hot passing through a 20 amp switch before the SSR. Not sure what I was thinking there....

I'll use 16awg after the fuses to the PID and pump

Can't wait to see your drawing. No rush tho. Patience is another thing I'm learning with this project...

Cheers

 

[Bobby_M]

My point was that this is not the correct application for that kind of switch, regardless if it is rated correctly or not (which I did not make very clear, btw) but thank you for pointing that out.

So the manufacturer has made a switch they claim is capable of switching 240v/30a and UL says "true". How is that unsafe? Are you suggesting that they should not make such a switch since under no circumstance should a 30 amp load be switched? I'm sorry that I'm not understanding you.

Since your opinion goes against the spec, you ought to be extra clear on why you think it's unsafe and perhaps quote some literature on the topic. In other words, you say that it is not the correct application for that type of switch. I ask this then, what IS the correct application for that kind of switch?

 

[crane]

Force of habit? Safety? To tell you the truth for me it has mostly to do with my personal acceptable level of risk. If I'm switching power, I want that switching to happen remotely inside of an enclosure. I have built large machines, and it is generally a no-no to switch devices under load, whether that is purely resistive or reactive. If I was to design a system for an electric brewery it would be with a contactor. If you are comfortable using a light switch, and it is working for you, there is no real reason to change it. As I say with anything that I do whether it is in personal or professional life - safety is the #1 priority.

Using your logic I would draw the conclusion that you have replaced all the light switches in your house with contactors?

 

[caseyw]

So the manufacturer has made a switch they claim is capable of switching 240v/30a and UL says "true". How is that unsafe? Are you suggesting that they should not make such a switch since under no circumstance should a 30 amp load be switched? I'm sorry that I'm not understanding you.

Since your opinion goes against the spec, you ought to be extra clear on why you think it's unsafe and perhaps quote some literature on the topic. In other words, you say that it is not the correct application for that type of switch. I ask this then, what IS the correct application for that kind of switch?

No worries, I will explain my reasoning. I have seen switches fail. I have seen contactors fail. Within their rated load, for their stated use. Because of this, I don't want my hand anywhere near the actual switching mechanism when I am turning on something that will be delivering or breaking instantaneous power draw. As I stated above, this has more to do with my personal acceptable level of risk than it does with whatever UL says.

It's well understood that when switches are opened or closed under load there can be small arcs or sparks inside the contacts. This can cause areas of oxidation, or material transfer between the contacts. I've seen this completely destroy contactors, sometimes even welding them shut. In industrial applications, great care is taken to design systems to de-energize prior to opening contacts for this very reason.

Maybe the switch is rated for the load? Sure. But why wouldn't the system designer just cut the power to the controller, rather than the load? This would stop the current flow and allow you to unplug the element safely. And then you can even use a cheap ole' light switch instead of that crazy hubbell thing

Again, point is that just because it can be done, doesn't mean it should be done. Conversely, I'm not guaranteeing that it won't work as designed, I just wouldn't design it that way - maybe I'm just being a wimp or the aerospace industry has made me overly sensitive to these things - I don't know

Does that answer your question?

 

[caseyw]

Using your logic I would draw the conclusion that you have replaced all the light switches in your house with contactors?

You have 5500 Watt lights in your house?

 

[r8rphan]

FTR, you were likely never in danger, as that is the point of having a GFCI breaker...

It measures current going out, comparing it to current returning, and if there is more than 15 milliamps difference, the GFCI knows something is going somewhere it shouldn't and trips...

It generally takes a minimum of 50 milliamps to get electrocuted, and that under ideal conditions...

So the GFCI trips long before you get any dangerous current going through you... and you can't wire them wrong, or else they trip when you try to energize them..

There's nothing wrong with using that switch.. That's the load and voltage it is intended for... It's a little towards the max end, and I generally like a little more headroom, but it's fine...

A contactor is sexy, but it really doesn't do anything different, except that it uses magnetic coil to close the contacts and a holding loop to keep them closed (if you want to use momentary push buttons to open and close the switch).. They are generally intended for switching high loads or for using a control output of some other device (ie a float switch) to energize them..

Whenever using any switch that is not one of the common SPST, 3 way or 4 way switches, I 'always' get out my ohmmeter and verify how it's wired internally... Just to make sure... Those switches aren't cheap...

Surprised you got that much of a 'boom' out of it all before the breaker blew... Must have been something in there to partially absorb the current.. The SSR perhaps?

I can tell that when it comes time to wire mine up, I think I'll run it all by everyone here and see if anyone sees any problems.. And I'm an electrician with more than 40 years of experience and formal training in commercial and industrial as well as residential...

So, don't feel bad about your screw up.. Even the pros screw up sometimes... Which is why I plan to have others double check my wiring layout.. Over the years I've learned not to take anything for granted...

Besides, I'm getting to 'that age' lol

 

[Firewalker11]

Funny how all of the electrical discussions end up with a bunch of pissed off people that want to save a few bucks. Its not Casey or I that are in charge of suggesting contactors, they are prescribed with big loads like these. A tap room with a small set up is not going to have a light switch controlling the elements, they will be contactors.

I know a lot of people bristle at the word "CODE" but why not? Think about it, a $25.00 30A light switch v.s. a $15.00 contactor?

What do you save? This is truly a silly discussion, use a contactor and be safe.

 

[Firewalker11]

FTR, you were likely never in danger, as that is the point of having a GFCI breaker...

It measures current going out, comparing it to current returning, and if there is more than 15 milliamps difference, the GFCI knows something is going somewhere it shouldn't and trips...

It generally takes a minimum of 50 milliamps to get electrocuted, and that under ideal conditions...

So the GFCI trips long before you get any dangerous current going through you... and you can't wire them wrong, or else they trip when you try to energize them..

There's nothing wrong with using that switch.. That's the load and voltage it is intended for... It's a little towards the max end, and I generally like a little more headroom, but it's fine...

A contactor is sexy, but it really doesn't do anything different, except that it uses magnetic coli to close the contacts and a holding loop to keep them closed (if you want to use momentary push buttons to open and close the switch).. They are generally intended for switching high loads or for using a control output of some other device (ie a float switch) to energize them..

Whenever using any switch that is not one of the common SPST, 3 way or 4 way switches, I 'always' get out my ohmmeter and verify how it's wired internally... Just to make sure... Those switches aren't cheap...

Surprised you got that much of a 'boom' out of it all before the breaker blew... Must have been something in there to partially absorb the current.. The SSR perhaps?

I can tell that when it comes time to wire mine up, I think I'll run it all by everyone here and see if anyone sees any problems.. And I'm an electrician with more than 40 years of experience and formal training...

So, don't feel bad about your screw up.. Even the pros screw up sometimes... Which is why I plan to have others double check my wiring layout.. Over the years I've learned not to take anything for granted...

Um.... No?

A GFCI is measuring current to GROUND, its not a amperage rated circuit breaker.

 

[caseyw]

Well, for what it's worth I am an Electrical Engineer.

 

[Firewalker11]

Well, for what it's worth I am an Electrical Engineer.

Casey, stay and teach, we need you here!

 

[r8rphan]

Um.... No?

A GFCI is measuring current to GROUND, its not a amperage rated circuit breaker.

Ummm, YES!...

Read what I said again.. I said 'difference' between what goes out and what comes back.. not current 'through' (which is what the standard breaker part itself measures)

This is 'indeed' how it works.. 'ground' is generally where the missing current goes. but it can go elsewhere, like another circuit.. Which is why it compares out to return and not to ground...

It is entirely possible to become part of a supply circuit to something outside of the supply circuit that is not ground.... and this is why they compare return to what went out..