VFD vs RPC......again

shell70634

shell70634

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Had a lightning strike a while back and still finding problems. My Clausing Kondia Bridgeport clone refuses to run. I haven't done any trouble shooting other than checking a magnetic switch I installed. Before I waste alot of time and energy diagnosing the damage, I need to consider buying a VFD. My mill is variable speed so VFD speed control is unnecessary. Ease of VFD installation versus trouble shooting RCP is the only benefit I can see. I am not capable of trouble shooting so I would have to pay someone or research and learn how. My question is: What are the benefits of the VFD over the RPC that I can't see?
The VFD I will probably buy is:
Are there any other components I will need? Other than wire and such.
 
VFDs are quiet, make speed adjusting far easier, and can do quick stop if a brake is added. BUT, I'd guess there's a good chance it will not solve what burned in the lightening strike.
 
I agree with Karl, You need to figure out what fried in the lightning strike before you start replacing components. Does the RPC turn on?
 
I'm assuming its the controller. It has power in but nothing out. My well controller is on the same meter and it was fried. Both use relays and capacitors. When it cools down this evening I will begin testing the individual components. I was asking whether I should just switch to a VFD instead of spending time, energy and money on a 1995 vintage phase converter system. And how is the VFD better than an RPC. I don't care about the speed adjusting ability as I have that mechanically on the mill. I just don't know if there are other advantages.
 
So you have a RPC now- no output? Idler motor running? If not then probably a relay got smoked
Going to a VFD is perfectly ok, you might spend some time programming it though
And remember you can't use any of the mill's electrical controls- all that stuff would need to be bypassed initially
The VFD needs to be wired direct to the motor- often the original controls can be wired to the VFD but that's a separate project
 
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capacitors are very likely... They often bulge or split when given way too much voltage. if you let the magic smoke out, they are bad.

do you have a volt meter? we can check for voltage at the relay coil. If its got volts and does not close its bad. Don't know where to check??? give us a couple pics of your control box.
 
If you were to operate at 60 Hz on a VFD, it would be the equivalent of running a RPC or being delivered 3 phase from a power company.

A vfd’s output goes directly to the motor without going through a control system, as the VFD ic the controller, where a RPC still requires a control system,

Multiple machines run best simultaneously from a RPC in comparison to a VFD
 
I've thought it out and will repair the rpc. I like the controls on the machine and haven't found any benefit from a vfd in my situation. It'll be a while before I get to it. I stupidly exceeded my body's limitations by working in the sun all day yesterday. Today is an AC day.
Thanx for all the input.

Shelly
 
shell70634 said:
I've thought it out and will repair the rpc. I like the controls on the machine and haven't found any benefit from a vfd in my situation. It'll be a while before I get to it. I stupidly exceeded my body's limitations by working in the sun all day yesterday. Today is an AC day.
Thanx for all the input.

Shelly
Click to expand...
I for one am glad to see you selecting the RPC. There is something to be said for plugging a machine in and using it the way it was intended. Cutting up and rigging everything else just to make cheap power conversion work on the motor is a weak reason to do it. A total overhaul may favor VFD, but who wants to completely gut and re-wire a machine that already works as designed?

I think :rolleyes: that lightning exceeds the rated voltage, but capacitors can only store electrons at the charge rate. Are blown caps after donnerschlag und blitzen even a thing? Seems the impulse duration would be a little short when caps are rate limited.
 
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