What's new
What's new

Monarch 10ee breakers size

pier

Plastic
Joined
Feb 25, 2015
What is the correct two poles breaker size for a 1942 10ee with MG drive?

The MG was modified from 3 phase 220 Volts to a single phase 220Volts
 
What is the correct two poles breaker size for a 1942 10ee with MG drive?

The MG was modified from 3 phase 220 Volts to a single phase 220Volts
Are you asking about the circuit breaker in the panel that supplies power to the machine, or something on the machine itself?

Cal
 
Are you asking about the circuit breaker in the panel that supplies power to the machine, or something on the machine itself?

Cal

I am asking about the breakers in the panel that supply power to the machine.
The lathe itself does not have any breakers. My breakers seems to pop off once in a while even if the lathe is just siting there running but not doing any cutting.
 
I am asking about the breakers in the panel that supply power to the machine.
The lathe itself does not have any breakers. My breakers seems to pop off once in a while even if the lathe is just siting there running but not doing any cutting.
A 30A breaker works for me as well, but the machine should only draw large amounts of current when the MG is coming up to speed. If a breaker is tripping when the machine is idling, something else is going on.

When you say that the machine was converted to single phase, what do you mean? How was that done? Pictures would be helpful.

Cal
 
Ok, I only wanted to know what is the general size of the two pole breakers used in the electrical panel when the 10ee is powered by a single phase 220V and with the MG modified as per the "sticky" Thread "Single Phase Conversion" on this site, and which I followed step by step.

Just to give you more details of my setup is as follows:
1) The two poles breaker in my panel is a Square-D 30 Amps
2) I have an extension cord (10 feet long) going from a 30 Amp plug directly to the lathe
3) The extension cord wire size is 10 AWG
4) modification of the MG uses the Start and Run capacitors and the SUPCO relay, just as described in the thread above "Single phase Conversion". This modification seems to work Ok so far. The only issues I had in the past was, that I measured very high voltages across both the Start capacitors and Run capacitors, but nothing ever blowed-up.

10ee-p1.jpgMG-Mod1.jpg

I am attaching a couple of photos showing the re-conditioned lathe and the panel showing the MG electrical modification.

Also, I want to mention that all bearings were replaced and every moving parts in the MG and DC motor was inspected for wear and tare, and there is nothing creating high friction.
 
I have to say that was a pretty clean job of installing that conversion.
My move would be perhaps to remove it, and use a rotary converter.

The paint job, thats unique!

Looking at the machine over all, it looks pretty good!
Good examples of machines that have been beat to hell, were sold off at Hanford and Boeing some years ago, the info plates at control and gear box locations get beat up so bad, its hard to read them.

I remember when this was brought up over 10yrs ago, I found it interesting at the time, but wanted to be able to use 3phase when available. I remember a couple of people did it, but not anything else until now. I dont know if anyone is still around or alive that did this.

Great photos, but, they may bother one sensitive person! The lathe is too nice, so look out!

Thought about it some more, I think I like the paint.

I have had big capacitors explode in static phase converters, they put them in a box for a reason, I would for sure wear a face shield working around them.
 
Ok, I only wanted to know what is the general size of the two pole breakers used in the electrical panel when the 10ee is powered by a single phase 220V and with the MG modified as per the "sticky" Thread "Single Phase Conversion" on this site, and which I followed step by step.

Just to give you more details of my setup is as follows:
1) The two poles breaker in my panel is a Square-D 30 Amps
2) I have an extension cord (10 feet long) going from a 30 Amp plug directly to the lathe
3) The extension cord wire size is 10 AWG
4) modification of the MG uses the Start and Run capacitors and the SUPCO relay, just as described in the thread above "Single phase Conversion". This modification seems to work Ok so far. The only issues I had in the past was, that I measured very high voltages across both the Start capacitors and Run capacitors, but nothing ever blowed-up.

View attachment 241870View attachment 241871

I am attaching a couple of photos showing the re-conditioned lathe and the panel showing the MG electrical modification.

Also, I want to mention that all bearings were replaced and every moving parts in the MG and DC motor was inspected for wear and tare, and there is nothing creating high friction.

Here are some thing to check You need to check the amps that the MG is drawing when running also the voltage to, as a low voltage will cause it to draw too much amps and trip the breaker. You also need to check the connections at the breaker to make sure they are tight and any connections in between.
 
All good advice, in general, but since Pier loaded-up the full info set, I'm one taking it as a given he has already done these things - and more.

It's that unpredictable, intermittent trip-out that is the mystery to be tracked-down and "addressed" in some manner that improves the situation.

That he has reported it only when in standby/idle, AND NOT when under load, in the cut, hints that it is of fairly low-level at-source, as even if arriving only episodically, it is "pushed own into the noise" when the MG is hauling even a modest load. So long as there IS a load, not just standby, it has not been reported as arising as a trip-out, EVEN though - the breakers are already carrying a higher load to support the load in the cut, hence have lesser reserve to use-up to reach the zone for tripping the breaker.

BTW - hope and TRUST that there are NO "GFCI" nor newer combined-fault cousins in this chain.

They can "be there", but they need more careful selection than ordinary residential dwelling service requires.

Absent that extra vulnerability to faux trip, this is where the 'scope could reveal the waveform, and spot the characteristic of DC Drives, VFD, or nasty switching compressor contactors. That could rapidly narrow-down where one has to go search for the truant device.

Hopefully, all that really needs is to go across the room and de-power some other device already ID'ed as a possible suspect, then see if the problem has just then gone away. No 'scope required!

Mind, mention of even using classical test equipment will also draw another round of hobby project photo attention-bid, but there's no great harm in that.

Our man in Walla Walla is at least rather good with a camera!

:)
Yep But did he pull the breaker and check the connection to the buss bars?
 
donie, thermite, PLEASE lay off the bickering! You're not helping the community with this stuff.

I went through the thread and deleted the off topic comments directed at each other. I saved what I could of donie's shop photos to https://www.practicalmachinist.com/vb/monarch-lathes/shop-tips-project-photos-356890/

I don't have time to sift through your posts and try to save the things that actually apply to the topic at hand, so when I see you guys going at it, I'm just going to delete the posts.

Cal
 
That is a good start, my only interest in this situation would be for it to be a sharing of information forum, as it was at one time. It has unfortunately become a forum of one dictator.
Early on here, there was very little information on these machines anywhere, or the drives, as more of the machines were released to the public, the mystery's of the drives through the years were solved.
Unfortunately, the forum has devolved to mostly very old machines, I doubt one person in particular can contain his jealousy to allow anything else but the old old stuff.

I need to ad, a deplorable non union individual such as myself, or anyone else can not start a thread here without it quickly being polluted to a point of WHY BOTHER.

Anyway, the only advice I can give to the OP is toss the gizmo.
 
Just to give you more details of my setup is as follows:
1) The two poles breaker in my panel is a Square-D 30 Amps
2) I have an extension cord (10 feet long) going from a 30 Amp plug directly to the lathe
3) The extension cord wire size is 10 AWG

Be careful with that 10ga extension cord - if it's one of the highly flexible cords with an SJOOW spec it might not be rated above 15-20A.

And it's likely the surge current starting that motor popping the breaker. I had a nice little setup to drive a compressor that doesn't draw 22 amps max when running but was delighted to pop a 30A breaker ever time on start. I had to repull 90' of wire and go to a 40A breaker to make it happy.
 
Russ,

I don't think it's a current inrush issue. He said it happens at idle:



Cal

Huh. I think I'd put a meter on that puppy, see if the current is surging to the 30A periodically as that can add up in the breaker. It might be just a bad breaker, even. Cheap enough to replace as a test.

I'd still be concerned about the extension cord - 10ga solid is good for the current (and more) but the more you divide the wire the lower the max sustained current gets. A nice floppy core in an OOW case might have a quarter of the spec of the same in a stiff solid wire.
 
Agree. I was about to suggest that he measure the current on both legs and see what's going on. That motor should have about a 14A rating at 240V. Even if it's running at full load with a power factor of 0.8, that's still only about 20A. A typical 30A breaker can take 40A for a minute or more before it trips. So something weird is going on. Maybe a bad breaker or bad run caps?

pier, Do you have access to a clamp-on ammeter? Are there fuses in power connection box on the back of the machine? Does the main AC contractor have overload protection?

Cal
 
Hi CAL

Right now I don't have a clamp Amp-meter that I could trust. My previous B&K 350B that I bought on ebay gave me wrong readings, so I am basically ignoring its existence.

First, I want to point out that I did perform the single phase conversion on this lathe because I don't have three phase power here at home. I moved the lathe a couple years ago from the shop (in there we have three phase power), and then decided to re-conditioned, so I could use it at home for small projects. The conversion process was easy and smooth, including taking the stator winding out of the generator casing. That process also gave me a chance of determining the state of the wires and coils (which was very good).

I was contemplating of buying an RPC to power up the lathe, but then decided not to, given that, "That's another unit running" and therefore, not being 100% efficient, will demand a bigger breaker circuit in the panel, and currently the electrical panel it's over his design capacity, so I need to be careful of what is being used at home before I turn the lathe on.

The power quality in my neighborhood is very clean otherwise, there are no shops or other industries around my street that could make the grid fluctuate that much.

Currently I am strongly suspecting that it is the breaker, but I don't want to replace it, unless I know for sure that it is the problem. This is the reason that I came to the web site to ask what size of breaker you require after the "Single Phase Conversion". I wish that some other people that perform that conversion will come forward and give their 2C. From my calculations, the 30 AMPs should be plenty, but who knows. In the shop when we had the three phase, the breaker size was 20AMP-3PH.

Cheers
Pier
 
Hi CAL

One more thing that I should mention:

What if the "SUPCO APR5" fails to disconnect the START capacitor, or it intermittently closes the contact due to some unknown reason, would this be a cause for over-current?

I kind don't trust the source of where I bought that relay (again, on ebay) so that is another of my suspects.

Is there a way to test the SUPCO APR5 relay by itself?

Is the adjustable voltage on the SUPCO relay the rms or peak voltage? Currently it is set to 250 Volts (because the instructions said to do that).

At one time I did notice the voltage across both the START and RUN capacitor to be very high, even after 30 seconds after power up, but I did not pay to much attention then, since things were running. But now, I find that to be abnormal because the voltage on the START capacitor should be zero after power up.

I do trust the capacitors because they are from a local vendor.

In my case I use 2 X 100uF-400VAC caps for the START (in parallel) and one 60uF-400VAC for the RUN cap.

Cheers
Pier
 
Hi CAL

One more thing that I should mention:

What if the "SUPCO APR5" fails to disconnect the START capacitor, or it intermittently closes the contact due to some unknown reason, would this be a cause for over-current?

I kind don't trust the source of where I bought that relay (again, on ebay) so that is another of my suspects.

Is there a way to test the SUPCO APR5 relay by itself?

Is the adjustable voltage on the SUPCO relay the rms or peak voltage? Currently it is set to 250 Volts (because the instructions said to do that).

At one time I did notice the voltage across both the START and RUN capacitor to be very high, even after 30 seconds after power up, but I did not pay to much attention then, since things were running. But now, I find that to be abnormal because the voltage on the START capacitor should be zero after power up.
If the potential relay fails to disconnect you'll know about it pretty quickly. Electrolytic starting capacitors can't survive very long when connected to line voltage.

I don't see any discharge resistors on your capacitors:
241871d1541739407-monarch-10ee-breakers-size-mg-mod1.jpg


When the potential relay opens the starting capacitors will sit there with whatever voltage they had at the moment they are disconnected from power. You might want to put a 100k Ohm, 1 Watt resistor across the terminals of the start caps to slowly discharge them. (Note, it will take the resistor over a minute to discharge the caps). Check the voltage across the caps once they've had time to discharge. If you're still seeing line voltage there, then something is wrong.

You should buy or borrow a clamp on ammeter to check the currents. You can get one from Amazon or HF for under $30 that will be good enough for what you need.

I do trust the capacitors because they are from a local vendor.

In my case I use 2 X 100uF-400VAC caps for the START (in parallel) and one 60uF-400VAC for the RUN cap.

Cheers
Pier
Peter's Stillman conversion diagram calls for three run capacitors (Cr and Cpf are run caps):
2073d1204511373-single-phase-power-motor-generator-10ees-small_figure_3.jpg

What diagram did you use to wire up your system?

Cal
 








 
Back
Top