Rex-c100; no proportional only on/off action

Thread Starter

Mullins

Joined Dec 31, 2021
179
Hi to all. I'm trying to set one Rex-c100 pid controller on my kitchen oven.
Before buying the controller I believed that the power supply to the heating resistor would be proportional. Now that I have mounted it and I have tried different combinations but the output always remains on/off. My Fluke clamp meter always shows the same value (10amp). Is it right for it to be like this? I thought that as the temperature reaches the target the amps would decrease.
 

Thread Starter

Mullins

Joined Dec 31, 2021
179
I confirm that this product is not able to moderate the consumption of the oven. Nonetheless, it keeps the temperature constant. All things being equal, it reduced cooking time by 30%. I'm still looking for a solution that will allow me to moderate my oven consumption. Please if you have any ideas tell me.
 

nsaspook

Joined Aug 27, 2009
13,446
I confirm that this product is not able to moderate the consumption of the oven. Nonetheless, it keeps the temperature constant. All things being equal, it reduced cooking time by 30%. I'm still looking for a solution that will allow me to moderate my oven consumption. Please if you have any ideas tell me.
It does moderate the consumption of the oven by using PWM. The thermal lag smoothing effect between on/off cycling is the time based equivalent (but not as accurate) to AC current/power control regulation. You won't gain much by going to to AC phase-angle control if the temp control is good now.
https://www.tempco.com/Tempco/Resources/13-Temp-Control-Resources/SCRPwrCntrllrCatalogPagesT.pdf
 

Thread Starter

Mullins

Joined Dec 31, 2021
179
the action of my own is only on and off. the consumption is 0 or 10amps. there's no pwm or thig like this
 

nsaspook

Joined Aug 27, 2009
13,446
the action of my own is only on and off. the consumption is 0 or 10amps. there's no pwm or thig like this
What does that mean? Sure, if it only stays off or on without ever switching again but that's not what the controller is doing if it's regulating to the setpoint.
 
Last edited:

boostbuck

Joined Oct 5, 2017
556
the action of my own is only on and off. the consumption is 0 or 10amps. there's no pwm or thig like this
If that is the case, how is it maintaining the set temperature? There must be some control action operating or the temperature would just rise to maximum (or more!),

Perhaps the PWM frequency is too high for your measurements to discern??
 

boostbuck

Joined Oct 5, 2017
556
I'm not familiar with the nuances of clamp meters, but is the meter perhaps showing PEAK value rather than average? To show a pwm controlled value the average reading would be needed.
 
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