On/Off switch (magnetic contactor) for VFD power supply

[CanFire]

Hi. I noticed in the Huanyang VFD documentation that it states:

"Electromagnetic contactor:Note: Do not use the electromagnetic contactor as the on/off button of power supply for
the inverter."

I was planning to do exactly that. Another fellow has already done it here: http://www.5bears.com/vfd02.htm

The manual does not say 'Do Not use on/off switch', but specifically states not to use an electromagnetic contactor as the on/off switch. Does anybody know why?

 

[Ray C]

Don't know the answer and this is precisely why I'm not a big fan of Huanyang VFD. -The manual sucks and gives no useful information. I'm still trying to figure-out how the jog settings are supposed to work for both fwd and rev mode. One slight problem though, is they are one of the very few VFD makers that output 5HP from single phase input. Most others only go up to 3 HP.


The Hitachi documentation is very good and informative. You might want to track it down and see if you can glean information from it.


Ray

Hi. I noticed in the Huanyang VFD documentation that it states:

"Electromagnetic contactor:Note: Do not use the electromagnetic contactor as the on/off button of power supply for
the inverter."

I was planning to do exactly that. Another fellow has already done it here: http://www.5bears.com/vfd02.htm

The manual does not say 'Do Not use on/off switch', but specifically states not to use an electromagnetic contactor as the on/off switch. Does anybody know why?

 

[CanFire]

I'm still trying to figure-out how the jog settings are supposed to work for both fwd and rev mode.

Ray, this guy has jog working on his lathe: http://youtu.be/4YOZHcoSNfQ?t=1m51s .Maybe you could post a comment asking for more info?

I just can't understand the reason behind wanting jog though. On a mills power x,y, or z feed I can see it being useful for positioning, but then you could always just use the speed potentiometer for the same thing. Would you mind explaining how you intend to use the jog function and on which machine?

Regards,
Dean.

 

[righto88]

Use a 2 pole disconnect switch installed after the fused L1 and L2. Or a fused disconnect switch and feed it.
Still use the Run/Off switch but if the contactor fails, ie, contacts stick together, you still have a means of shutting power off.
Keep it (the disconnect) with-in sight of your machine.

 

[righto88]

A key point:
"Do not use the electromagnetic contactor as the on/off button of power supply for the inverter"
Where is the supply coming from?
L1 and L2
via the run/stop, on/off, start/stop, (whatever it is called) switched contactor.
Tech talk for having a place to remove "applied power". Or should I say "the source of power"?

 

[Ray C]

Thanks... I'll check that info about the jog.Jog is really handy for changing gear setting on some lathes. To change the gear speed on my machine, it must be stopped first then, the gear levers are manually changed. Sometimes, the gears do not line-up and you blip the motor for a split second to move the gears just enough so you can move the lever. This happens to me 10 times a day at least. For now, I just manually spin the chuck by hand but sometimes that's almost impossible to do if the gears are in a very low ratio.Also, all my chucks have witness marks to align with a mark on the spindle. It's darn hard to grab the spindle and turn it by hand to rotate it to a desirable position so a chuck can be installed in the preferred position.-Many other examples too. Especially when setting up a shaft for re-threading on the lathe. -Especially if it's a metric thread where you cannot let the halfnuts loose.Ray

Ray, this guy has jog working on his lathe: http://youtu.be/4YOZHcoSNfQ?t=1m51s .Maybe you could post a comment asking for more info?I just can't understand the reason behind wanting jog though. On a mills power x,y, or z feed I can see it being useful for positioning, but then you could always just use the speed potentiometer for the same thing. Would you mind explaining how you intend to use the jog function and on which machine?Regards,Dean.

 

[CanFire]

A key point:
"Do not use the electromagnetic contactor as the on/off button of power supply for the inverter"
Where is the supply coming from?
L1 and L2
via the run/stop, on/off, start/stop, (whatever it is called) switched contactor.
Tech talk for having a place to remove "applied power". Or should I say "the source of power"?

Thanks for the reply, but I'm not sure what you're getting at. I was planning to wire it almost exactly like 5bears did in the link I posted in my first message. I intend to use an electromagnetic contactor as a means to turn on & off the power (L1 & L2) that supplies the VFD. The manual however, seems to say that this is a bad idea. I just don't understand why an electromagnetic contactor is singled out as bad, but other types of switches seem to be OK. I can't leave the VFD running all the time and turning it on & off via a 50-amp breaker is a bad idea.

Cheers!

 

[righto88]

Thanks for the reply, but I'm not sure what you're getting at. I was planning to wire it almost exactly like 5bears did in the link I posted in my first message. I intend to use an electromagnetic contactor as a means to turn on & off the power (L1 & L2) that supplies the VFD. The manual however, seems to say that this is a bad idea. I just don't understand why an electromagnetic contactor is singled out as bad, but other types of switches seem to be OK. I can't leave the VFD running all the time and turning it on & off via a 50-amp breaker is a bad idea.

Cheers!

You must not be reading your PM, ie private messages.

 

[righto88]

I can't leave the VFD running all the time and turning it on & off via a 50-amp breaker is a bad idea.


Where is this located at with respect to "your machine"?????

the 50 amp breaker? I never said to use that as an on/off switch but as a means, a source, a place to stop all source of implied power, ie voltage or cause of,,,,,

 

[CanFire]

the 50 amp breaker? I never said to use that as an on/off switch but as a means, a source, a place to stop all source of implied power, ie voltage or cause of,,,,,

I didn't mean to imply that you had suggested it. The outlet that I use for my mill will be the same outlet that I occasionally use for my welder and it is a 50-amp circuit. From the manual, it almost seems like Huanyang wants the VFD hardwired in and left running 24x7 or to use the circuit breaker as an on/off switch - which in my mind is a bad idea.

My apologies for the confusion. You were right - I hadn't noticed that I had been getting PM's.