adccommunitymod (AutomationDirect) asked a question.
Created Date: May 21,2016
Created By: Mario
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Guys, what's the difference between a varistor and resistor-capacitor circuit when it comes to surge suppressors in AC coil contactors? I'm using WEG Electric CWC series miniature contactor, 16 amps, 3 N.O. power poles, coil voltage 120VAC, 1 N.O. auxiliary contact. They are driven by triac C0-08TA, CLICK discrete output module, 8-point, 17 - 240 VAC, 2 isolated common(s), 0.3A / point. I'm expecting to have between 300,000 and 500,000 cycles per year, and shortest cycle on some contactors is 10+ seconds, while the longest period on other contactors is 1 minute to 11 hours. Surge suppressor, resistor-capacitor circuit, 50-127 VAC, 50-60 Hz. Use with CWC07 to CWC025 contactors. http://www.automationdirect.com/adc/Shopping/Catalog/Motor_Controls/WEG_Electric_Miniature_Contactors_(3-Pole)/7_Amp_(AC3)/RCC0-3D55 Surge suppressor, varistor circuit, 50-127 VAC 50-60 Hz, 60-180 VDC. Use with CWC07 to CWC025 contactors. http://www.automationdirect.com/adc/Shopping/Catalog/Motor_Controls/WEG_Electric_Miniature_Contactors_(3-Pole)/7_Amp_(AC3)/VRC0-2E34
Created Date: May 21,2016
Created by: Mario
Guys, what's the difference between a varistor and resistor-capacitor circuit when it comes to surge suppressors in AC coil contactors?
I'm using WEG Electric CWC series miniature contactor, 16 amps, 3 N.O. power poles, coil voltage 120VAC, 1 N.O. auxiliary contact.
They are driven by triac C0-08TA, CLICK discrete output module, 8-point, 17 - 240 VAC, 2 isolated common(s), 0.3A / point.
I'm expecting to have between 300,000 and 500,000 cycles per year, and shortest cycle on some contactors is 10+ seconds, while the longest period on other contactors is 1 minute to 11 hours.
Surge suppressor, resistor-capacitor circuit, 50-127 VAC, 50-60 Hz. Use with CWC07 to CWC025 contactors.
http://www.automationdirect.com/adc/Shopping/Catalog/Motor_Controls/WEG_Electric_Miniature_Contactors_(3-Pole)/7_Amp_(AC3)/RCC0-3D55
Surge suppressor, varistor circuit, 50-127 VAC 50-60 Hz, 60-180 VDC. Use with CWC07 to CWC025 contactors.
http://www.automationdirect.com/adc/Shopping/Catalog/Motor_Controls/WEG_Electric_Miniature_Contactors_(3-Pole)/7_Amp_(AC3)/VRC0-2E34
Created Date: May 21,2016
Created by: Do-more PE
MOV's will "wear out " with each spike that they snub. They are best for minimal use although they do a better job at suppression.
The RC circuit has to be tuned to the contactor coil. These are a are best for circuits where there will be a lot of activity.
In your case, you probably should go with the RC circuit since you will be exercising the contactor so often.
Created Date: May 21,2016
Created by: Mario
MOV's will "wear out " with each spike that they snub. They are best for minimal use although they do a better job at suppression.
The RC circuit has to be tuned to the contactor coil. These are a are best for circuits where there will be a lot of activity.
In your case, you probably should go with the RC circuit since you will be exercising the contactor so often.
Sweet, thanks.
Created Date: May 22,2016
Created by: kewakl
The voltage at which a MOV begins to conduct may be significantly higher than the voltage at which the RC begins to dissipate the energy.
Created Date: May 25,2016
Created by: genebond
Way back, I did a lot of testing on the difference. An MOV is considerably slower at snubbing the spike, allowing a much higher peak to result. I highly recommend using the R-C circuit.
Created Date: May 25,2016
Created by: Mario
Way back, I did a lot of testing on the difference. An MOV is considerably slower at snubbing the spike, allowing a much higher peak to result. I highly recommend using the R-C circuit.
Thanks for that info.
Yeap, that's what I ended up ordering for Thursday's job.
RCC0-3D55
Surge suppressor, resistor-capacitor circuit, 50-127 VAC, 50-60 H...