JLD 615

[lcastanheiro]

Hi, can I use this controller in the following situation?

Control a smoking chamber that is maintained at 160 deg F (temp sensor 1) that has sausages with a temp probe (temp sensor 2) inserted in it.

The control would be like this:

run heater for 3 hours and maintain space below 100F.
Then
Run heater to heat the space, if the temp reaches 160F detected by sensor 1 stop heating element, when temp drops from 160 F start heating element, continue to heat the space until sensor 2 reaches 150F then stop heating element and stop control routine.

my heater draws around 15 amp, how would I hook this PID to an SSR if its output is Relay output (3A 120V AC). This output can't drive the heater directly due to the amps.

I appreciate your help.

Thanks

[richiem]

I don't see how; but the manual for the JLD615 is too sparse on details for me to be sure. If it would work, you would have to use the single internal relay to operate an external relay (or SSD) using an external power source.

I think it's easiest to use two controllers and two SSRs -- one JLD634 ramp/soak controller to hold the chamber just below 100 deg for the three hours then run the temp up to 160 and hold; and one JLD612 to cut off the heat when sausages get to 150 deg.

The controllers will each drive an SSD -- with the heater, SSD1, and SSD2 all in series with each other. When SSD2 -- controlled by JLD612 -- is sensing below 150, it is on. When SSD1 -- controlled by the JLD634 -- is sensing something above some minimum temp but less than 100 for the first three hours, it is on too; then after three hours when it is sensing less than 160 it is on. Both SSDs are therefore on or controlling the set point (on & off, as needed) and when they are both on, so is the heater. When either SSD is off, the heater is off.

For the rest of the control details, the manuals should provide the info you need.

[lcastanheiro]

Hi Richiem,

I think I got your reasoning.

Generating smoke make make the temp in the smoke box to go way past 100F so I thinkl its better to generate it in an outside box and pipe the smoke in. My question is. Is there a more elegant way of doing it instead of using the manual swicth MS. It kinda takes away the auto control.

I appreciate the suggestions.

Thanks.

[richiem]

Perhaps you generate all smoke and heat from the smoke box -- then use one probe-PID-SSR to monitor/control heat in smoke box and one probe-PID-SSR to monitor heat in sausage and shut system down.

I'm sure there are several other ways to do this, including using a third PID to control the smoke generator separately from the control of heat in the chamber and sausages -- no real limit on complexity, but cost will probably become an issue....