Help with a 220v PID controlled smoker.

[river100]

I'm a little late for this post but my suggestion could give your smoker element and wire a longer life.
Decide on the highest temp' you want to run your smoker at once you get it going. Look at your PID manual and find a place that lets you set the max % output,0-100%. Do a test run setting the max% output to 75%,( not the same as max temp'), Set the smoker to the max temp you want to run your smoker. If it gets to target temp' in a short enough time you've just lowered the chance of a current /heat related issue and gave life to the element and wiring.
If it doesn't get to the target temp' start raising the max% output until it does it in a resonable amout of time.
You can go as low as the element will hold the setpoint temp' and you're ok with how long it took to get there. If you're cooking large amount or filling the smoker you might need "headroom" in your max% output setting so dont't forget that. If you end up with 80, your element will never get over 80% of it's rated wattage, 4000 watts for a 5000 watt element.
How much of a difference this makes depaends on your setup. If your element can barely get the job done at 100% output there's no sense in even doing this.
Another limitation is the Max% output setting, some cheaper PIDs may not have that setting.
You will probably need to make adjustment to the PID tuning if you change the max output.

 

[dward51]

I'm a little late also.... You need nickel coated copper wire with either mica glass insulation (Type MG) or Type TGGT. Those both have insulation rated to 482 degrees F.

You also need to use special high temp nickel crimp on terminals, and a hydraulic crimp tool is the best way to go. The nickel is not going to oxidize like bare copper will. Once the connection starts to oxidize, the resistance increases at that point, and the amp carrying capacity falls of quickly. Soon that junction will overheat and start a cascade of failures like what you had happen. Wire nuts are not rated for this and solder can melt also. Basically any wire junction not super high temp rated needs to be outside that chamber (wire nuts or Wago connectors).

I would also go with a SSR and heat sink for the SSR that are rated higher than the amperage you expect to switch. For example, 5,000 watts at 220v is actually 22.73 amps. So I would go with a 30 amp or greater SSR and sink rated for 30 amps. Also a 20 amp 220v breaker will likely be tripping, so you would need to go 30 amp there as well (and insure any wiring is rated for AT LEAST 30 amps). You don't need to oversize the SSR trigger wiring from the PID as it's just a trigger signal and very low amperage. Same for the power to the PID, but if you pull power to the PID off one of the legs of the 220v in the body of the smoker, make sure to fuse that power wire to the PID to protect the gauge wire you use to the PID (probably a 3amp fuse will work).