Hello All,
I would like feedback for a project I am attempting to get pushed through at my job.
Background:
We currently employ 3 phase contactors to control 3 heaters each (wired in delta) as part of a zone. As an example, Zone 1 has 10 total heaters, therefore 4 contactors. The voltage is 480VAC 3phase. Each leg from the contactor reads approx 10A during operation. Each heater is 3kw. They are resistive elements similar to an standard domestic stove.
The Oven has 6 zones. A thermocouple closes a contact which activates (energizes the contactor coils) the entire zone or deactivates it depending on the temp set point and allowed variance. (present schematic attached)
The Vision:
My idea is to replace the 18 contactors that operate the zones and run each zone with an SCR, using the same heater config. The SCR would be controlled from a micro controller running a PID loop and outputting a 4-20mA signal.
My question concerns the benefit of this scheme versus the present. I hope to improve control and perhaps save some energy in the process.
I welcome ideas and feedback. I am still learning about these devices.
I would like feedback for a project I am attempting to get pushed through at my job.
Background:
We currently employ 3 phase contactors to control 3 heaters each (wired in delta) as part of a zone. As an example, Zone 1 has 10 total heaters, therefore 4 contactors. The voltage is 480VAC 3phase. Each leg from the contactor reads approx 10A during operation. Each heater is 3kw. They are resistive elements similar to an standard domestic stove.
The Oven has 6 zones. A thermocouple closes a contact which activates (energizes the contactor coils) the entire zone or deactivates it depending on the temp set point and allowed variance. (present schematic attached)
The Vision:
My idea is to replace the 18 contactors that operate the zones and run each zone with an SCR, using the same heater config. The SCR would be controlled from a micro controller running a PID loop and outputting a 4-20mA signal.
My question concerns the benefit of this scheme versus the present. I hope to improve control and perhaps save some energy in the process.
I welcome ideas and feedback. I am still learning about these devices.
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