L8TRG8TR
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- North Fort Myers,fl
Chipper 380 v
- Thread starter L8TRG8TR
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petersonra
Senior Member
- Location
- Northern illinois
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- engineer
have you considered a transformer feeding a VFD?
its probably 380V, 50 Hz.
or replacing the motor? might be cheaper.
its probably 380V, 50 Hz.
or replacing the motor? might be cheaper.
L8TRG8TR
Member
- Location
- North Fort Myers,fl
the cabinet feeds the mitsubishi Sent from my SGH-T889 using Tapatalk
L8TRG8TR
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- Location
- North Fort Myers,fl
Heres where im con fus
Here's were I'm confused the inverter
132 amp input its feed from the controller but the controller is fused at 125 amps
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Here's were I'm confused the inverter
132 amp input its feed from the controller but the controller is fused at 125 amps
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- Location
- San Francisco Bay Area, CA, USA
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- Electrical Engineer
Well, that panel has all kinds of wrong going on in there, so the odd fusing is not surprising. But fusing is not as critical (from an installation standpoint) as the conductor sizing. The NEC says that the conductors FEEDING that VFD must be sized for 125% of the VFD maximum nameplate input amps, not the motor amps. That drive is rated for 138A maximum input, so the conductors must be sized for 173A minimum. We're talking 2/0, and that doesn't look like 2/0 in that photo.
But as to fusing, the mfr will have a MAX fuse size specified, but you can use smaller if you like. If you notice, the OUTPUT current rating of that drive is only 57A at heavy Duty (HD), which is how that drive should have been applied. So assuming then that it is a 40HP motor, 125A fuses would be fine. But that is at 480V, you only have 230V. So you will need a transformer for this to step it up to 480. Since you have a VFD and therefore very low starting current, you can likely get away with a 75kVA. The input on the 240V side will end up at about 180A max, so you're going to need a 225A breaker feeding it.
Forget the stinger leg issue, it's irrelevant.
But as to fusing, the mfr will have a MAX fuse size specified, but you can use smaller if you like. If you notice, the OUTPUT current rating of that drive is only 57A at heavy Duty (HD), which is how that drive should have been applied. So assuming then that it is a 40HP motor, 125A fuses would be fine. But that is at 480V, you only have 230V. So you will need a transformer for this to step it up to 480. Since you have a VFD and therefore very low starting current, you can likely get away with a 75kVA. The input on the 240V side will end up at about 180A max, so you're going to need a 225A breaker feeding it.
Forget the stinger leg issue, it's irrelevant.
kwired
Electron manager
- Location
- NE Nebraska
I read the nameplate to mean anything between 380 and 480 volts as being acceptable and either 50 or 60 Hz. This would make it usable on the common 480 volt system in North America as well as on the 415 volt systems in Europe.
Add: that is the rating for the drive, you may want to check rating of the motor and any other components to make sure it will work for your application.
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The 138A in and 71A out doesn't sound right unless a very peaky input current is assumed. Even then.............dunno, not something I've seen in practice.
It's nominally 400V in the EU zone these days.
petersonra
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- Northern illinois
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- engineer
I do not know why but the ratings of Japanese made VFDs often seem to have this kind of rating where the input far exceeds the output. This does not seem to be an issue on US and European made drives.
It makes for some strange input wiring for those used to US made VFDs.
It makes for some strange input wiring for those used to US made VFDs.
L8TRG8TR
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- Location
- North Fort Myers,fl
I have a pdf hand written drawing looks like the guy wrote 3x70 at 400v to feed the control box
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L8TRG8TR
Member
- Location
- North Fort Myers,fl
L8TRG8TR
Member
- Location
- North Fort Myers,fl
This is that draeing see what you guys think
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- San Francisco Bay Area, CA, USA
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- Electrical Engineer
I think what he is showing is meant to be 3 x 70mm2 cables. Remember, he is saying 400V which means this came from a metric guy, so his notations cannot be taken literally because we have different rules.
70mm cable is roughly the equivalent of 3/0 cable here.
Take a step back and start with the MOTOR nameplate amps and volts. Everything important here starts with that.
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