[asymptonic]

Presumably the difference is in the PWM. In the Q models it's provided externally by the inverter. In the M models it's done in the contactor. I'm guessing Gigavac tuned the PWM in the M model for efficiency. Maybe worth emailing Gigavac to ask for more ideal settings?

 

[asymptonic]

The spec sheet references this application note which may help.

 

[asymptonic]

Yeah, I plan to spring for the dual coil version in my build and either ignore the supplied one or use it for some other infrequent purpose.

 

[asymptonic]

It's really just micro-vibrating. Kind of like connecting a small DC motor to a source of audio signal - it will play it like a speaker.

Then you may be hearing vibration of the coil. But yeah, Gigavac is expecting you to be able to set the PWM frequency outside of human hearing range (hence 25khz). It looks like you can't do that in the SME software.

 

[asymptonic]

I'm curious since you have the software in hand. Can PWM be disabled in the interface or is the SME software hard coded to do that? Trying to see if a contactor with built in economizer or dual coil is even possible.

 

[asymptonic]

It can't be disabled (at least not for me although it's the OEM version) since the inverter needs to output the signal for the contactor. If there is any fault, it jumps into failmode in order no HV is passing through. So I think it's kind of a safety feature (bug ).

I just meant can the PWM be disabled, not contactor control. Like set to 0hz or something. Otherwise I'd want to think about some PWM detecting relay to convert to a solid voltage to avoid PWM.

 

[asymptonic]

Dang.