Thread: Wiring up the Rivett...but no diagram...:-(

Hi there,

Try this one, this is a scan of the diagram that was folded up in the electrical cabinet on mine. It is high-enough resolution to read, though you may need to drag it out into another program to zoom in.

The diagram is redundant, there is a logical schematic on the left 1/3, and a physical layout schematic on the right 2/3. I can take a photo of my cabinet, but first I'll need to scan a copy of my diagram with my notes as to what I changed for the VFD conversion.

As to the neutral white wire, mine had one as well and I think at one time it went to wire an external receptacle for a lamp or something. It is not used for the 110v loads in the machine, those come off of the transformer, not from a hot-neutral pair.

I hope this helps!!

Originally Posted by rustygreen

Hi there,

Try this one, this is a scan of the diagram that was folded up in the electrical cabinet on mine. It is high-enough resolution to read, though you may need to drag it out into another program to zoom in.

The diagram is redundant, there is a logical schematic on the left 1/3, and a physical layout schematic on the right 2/3. I can take a photo of my cabinet, but first I'll need to scan a copy of my diagram with my notes as to what I changed for the VFD conversion.

As to the neutral white wire, mine had one as well and I think at one time it went to wire an external receptacle for a lamp or something. It is not used for the 110v loads in the machine, those come off of the transformer, not from a hot-neutral pair.

I hope this helps!!

rusty,

I think this does help, although I am still in question about the transformer that I don't appear to have. That is the big question at the moment.

I think we're going to try and trace it out today, so this should come in handy.

Thanks, news at 11:00 as they say...

Ok, here is a photo of my electrical cabinet. Comparing to yours, it does look like someone made some changes, and that transformer looks to be missing. It looks like your coolant pump contactor is where that transformer is in mine (and in the diagram). My lathe does not have the coolant pump. I'm also not sure why you have 4 of the small contactors rather than 2? Those are the fwd-rev contactors for the Reeves drive motor.



Here is the diagram copy that I marked up to keep track of my VFD conversion, so you can make sense of some of the differences you might see.

BTW, the spindle motor is the only 220v load in the machine, and the only 3-phase. The controls and the motor for the Reeves drive are all 110v single phase.

EDIT: (in yours, the coolant pump would be 220v 3-phase as well according to the diagram)

Is it possible that someone stripped that transformer out and wired the 110v loads with the neutral? Whether that is an ok conversion is beyond my ability to judge, since I'm not sure what the reason was behind using a transformer originally. Maybe the neutral wire is/was uncommon in industrial 3-phase lines?

This schematic diagram shows the more conventional case where the B phase has no protection (but the A and C phases do) and it is the A and C phases which are reversed.

Originally Posted by rustygreen

Ok, here is a photo of my electrical cabinet. Comparing to yours, it does look like someone made some changes, and that transformer looks to be missing.
It looks like your coolant pump contactor is where that transformer is in mine (and in the diagram). My lathe does not have the coolant pump. I'm also not sure why you have 4 of the small
contactors rather than 2? Those are the fwd-rev contactors for the Reeves drive motor.

Yes, just as we had suspected...it does seem I'm missing the transformer. We can only guess that the transformer was pulled out and a separate 115v line was run to power the controller. Not sure why they would have done that, or if there
would be a problem doing as was intended from the factory and adding the transformer back in. That is what we're leaning towards.

Originally Posted by rustygreen

Here is the diagram copy that I marked up to keep track of my VFD conversion, so you can make sense of some of the differences you might see.
BTW, the spindle motor is the only 220v load in the machine, and the only 3-phase. The controls and the motor for the Reeves drive are all 110v single phase.

EDIT: (in yours, the coolant pump would be 220v 3-phase as well according to the diagram)

Is it possible that someone stripped that transformer out and wired the 110v loads with the neutral? Whether that is an ok conversion is beyond my ability to judge,
since I'm not sure what the reason was behind using a transformer originally. Maybe the neutral wire is/was uncommon in industrial 3-phase lines?

Yes, but I actually do NOT have a coolant pump on my machine, per the plate and/or manual, so we're not sure why they would have put a relay in there.

Beyond my ability to judge also, and why I am getting help from a friend. The first diagram you sent had the size of the transformer (200va) and I found one on ebay for $35, but before I buy it we just want to make sure this is the right thing to do.

Thanks for your help rusty, much appreciated.

Originally Posted by rustygreen

Ok, here is a photo of my electrical cabinet.

rusty,

Thanks again for posting your electrical cabinet. I just ordered a transformer on ebay, found one that was very similar to what you have and what another lathe had it it.
The number is slightly different, but should be similar, and it is 240/480 primary and 120/240 secondary, with a 80 degree C rise.

The only difference is that the one I bought is KVA .250 rather than the KVA .200 which Rivett used.

Hopefully this will get the power straightented out and get my lathe spinning. Thanks for posting your pic.