Wiring up Push button Switch

This post is an addendum to the Cutler Hammer post from last week.

My research has yielded a bit more info, but not quite enough for me to be content.

CH 3 pole AC reversing push button switch No 9122H3A

* I found a label on inside of cover w/ a date a "Dec. 1947" Yikes!! It's old.

It also says...

Max HP Ratings Single Phase: 1 hp - 115v; 1.5 hp 230-575v
Max HP Ratings 3 Phase : 1.5 hp - 115v: 2 hp 230-575v

Now, I can't find any evidence of a control tranformer on the lathe. So I'm assuming this is/can be a FULL Voltage switch.

Secondly, JRaef stated in other post that I should be sure to confirm the current rating of the switch. This I have not been able to do.
But, would it be safe to assume that a typical 1.5 hp 3ph 220volt motor that draws 5.8 amps(this is on the motor data )plate would be safe to be controlled by this switch?
Is there a wide range of amperage draw among motors of this size?

Last night, I visited an electrical supply place in Laporte, IN on recommendation of some local guys who couldn't answer my questions. An older guy runs the place. I brought in my pictures/schematics asked my questions to guy at counter, no luck. He calls upstairs for the owner who comes down, listens to me and informs me that he'll sell me whatever I want but don't bother him or his people with questions they can't answer,"...that's what electricians are for."

Thanks, Paul

Paul,
are there three buttons on the front of the switch? FOR-STOP-REV.

JIM

Are you sure that your lathe doesn't have a reversing motor contactor in the cabinet? The push buttons would connect to this and then they would only handle the contactor coil current. Wiring diagrams are in motor control books and could also be found on the web.

Some of the older FWD/REV pb stations operated the switches directly mechanically, and there was a mechanical interlock to prevent going from FWD to REV without stop in between.
One up side is generally everything from that vintage was often made with what would be considered now as overkill, i.e. 'massive' amount of copper in the contacts, especiall when compared to the DIN style switches/contactors available now.
Minder.

would it be safe to assume that a typical 1.5 hp 3ph 220volt motor ... would be safe to be controlled by this switch?

Click to expand...

The short answer is no. Which isn't to say that it will not work, because it may work for a while. They aren't designed to be a motor starter, they are made to switch a low amp load, often at low voltage.

If you need something to use on a regular basis, you'll want to get a dedicated motor reversing switch.

Jim:

Yes, Fwd -Stop -Reverse...top to bottom

Minder:

You got it right. Switch operates mechanically w/ interlock, you have to hit stop before to change from fwd to rev for example.

Precision: I won't argue w/ your point about upgrading to a motor reversing switch, it's good advice. I'm in the process of getting the lathe running. But I had an electrician w/ a fair amount of experience (28 yrs) including a good amount of industrial control work look at this set up after work today. Short of suggesting the removal of an AB starter that isn't needed(see previous thread) he seemed to think it was fine. I realize advice is as good as the person giving it.

That being said, I'm propably going to replace it in the near future.

Thanks for the advice, Paul

re-think what you are considering

The motor starter is needed. The For-Stop-Rev coontrol is just acting as a d.p.d.t. switch. To reverse a three phase motor, you only need to incherchange any two phases. That is exactly what the pushbottons are doing.

Reggie: You are talking about the Allen Bradley starter, correct?
And "d.p.d.t."...double pole, double throw??

Sooo, if I need to keep the AB starter, then I suspect that I may have to change heater size in there as they are AB size N-17 heaters rated at 3.01 amps. The motor is rated at 5.8 amps. Could it be that the heaters were installed for 440v( the motor is 208/220/440)?
When I bought the lathe, we fired it up at company's shop which has 208 3 ph power.

Looks to me like a composite control system.

Line ---> Fusible safety switch ---> (nonreversing) magnetic motor starter ---> (reversing) snap switch ---> motor.

The snap switch is rated for the load, which is OK.

The other necessary functions are provided for by independent means (safety switch, starter).

A more expensive way to achieve the same function would be a reversing magnetic motor starter, but these take up much room and generally cost more than twice the cost of a nonreversing starter.


Square D made a motor starting snap switch which was rated 2 HP single-phase and 5 HP three-phase, and fit within a standard box. Rockwell used these on certain Unisaws and 20" bandsaws, and probably elsewhere, where the motor had integral overload protection.

Reversing was not a requirement for these Rockwell models.

The Square D switch is still in their catalog.

A snap switch which is designed for motor starting is rated in HP, and is perfectly fine when used within its nameplate rating.

You should check the coil voltage (could be 480) of the AB starter as well as sizing the heaters for the load at your shops voltage 208 or 240VAC. Yes, D.P.D.T. is double pole double throw and internally the For-Stop-Rev snap switch is wired to interchange two of the phases, thereby changing the direction of the motor rotation.

Recoiless;
Any way you could post a picture of your control station?
Since this is a 1947 vintage switch station it could be that it is design as a stand alone control. Alot of the older Rockwell and such machines we have at work have the maintained interlocked mechanical starters which sounds to me that this is they've just added the reversing contacts into it much like a reversing drum switch.
The company I work for has been in buisness since the 1800's and most of their "new" machines are of the 1940's vintage and I see alot of this.
I'm slowly updating these to more modern control but the going is slow.
Most of the old timers can't undrestand why something needs to be changed "'cause it's been working fine since for ever".

Jeff

jeff77indy said:

Most of the old timers can't undrestand why something needs to be changed "'cause it's been working fine since for ever".

Jeff

Click to expand...

Just tell the old timer that the stuff needs to be changed because it is older than he is and since he is almost dead.....

Jeff:

There is a pic on the 11-15 post titled "Cutler Hammer 3 pole switch" it's a shot of the backside of said switch. If you want, I'll post a pic of front, let me know

recoilless said:

Jeff:

There is a pic on the 11-15 post titled "Cutler Hammer 3 pole switch" it's a shot of the backside of said switch. If you want, I'll post a pic of front, let me know

Click to expand...

I looked at the picture on other thread.
It looks to me like there are two jumpers most likely reversing two phases from fwd. to rev. Much like a reversing drum switch.
If this is the case I would wire it the same way it is in the picture making sure the motor is wired to the correct voltage.
The motor starter is suppling the voltage either to the switch station or to the motor from the switch station but the switch station is controlling the motor.
Jeff

Jeff:
Yes, Motor starter IS supplying the pushbutton station and jumpers are for switching 2 phases. As soon as I get everything smoothed out, I'm gonna get a better starter(w/ 3 heaters, not 2).

recoilless said:

Jeff:
Yes, Motor starter IS supplying the pushbutton station and jumpers are for switching 2 phases. As soon as I get everything smoothed out, I'm gonna get a better starter(w/ 3 heaters, not 2).

Click to expand...

So it is basiclly working like a reversing drum switch then.
Are you going to stay with the control switches you now have or go with a three wire type control?
If so you'll need a reversing contactor and a three button momentary contact control station.
I've picked a few motor starters up off e-bay for some decent prices.
What voltage are you using to pull your starter in with?
Are going to use 480 volt 3 phase or 240 volt 3 phase for the motor?
Jeff