[OP]
Contributor
The line power on this Hammond Trimosaw comes into the Double D switch box, then goes to the toggle on/off switch on the front of the machine, then through the j-box on its way too the motor.
The motor is 3-phase 1 hp.
This seems to me like one step too far - I'm thinking of removing the DD switch box, but am I overlooking something?
IMG_5040.jpg IMG_5039.jpg IMG_5043.jpg
Thanks! Mark
Contributor
The Square D magnetic contractor would be the one I would keep. Some Other contributors are very knowledgeable saw about wiring.
Last edited by Maurice Mcmurry; 09-08-2022 at 8:03 AM.
Best Regards, Maurice
Contributor
Are you guys sure that the Square D box is actually a "magnetic switch". Not all switches were made to be magnetic. I do know that the switch on my Jet dust collector is NOT magnetic. It will stay engaged when power is cut and then the dust collector is automatically powered on when A/C power is restored. This is not an issue on something like a dust collector. However, it is a major safety issue for stuff like table saws. On something this old, it's possible that the switch is not magnetic.
You could look for an after-market 3-phase magnetic switch and then wire that directly to the motor (bypassing that on/off switch on the front).
[OP]
Contributor
Having a magnetic switch is not a huge advantage for me, it's just me in the shop, nobody else's fingers to worry about.
If that's the sole reason I'd as soon remove it.
Member
I fear I'm going to offer advice that isn't wanted, but I'll bet dollars to horse turds that the toggle switch on the front of that machine is NOT 3 phase, not 240V, nor is it rated for 1Hp. And if it is in fact used as an on/off switch, then it is only making/breaking the coil voltage, not the line power. And so the Double D* box is in fact a magnetic 3 phase starter - hopefully with overloads (heaters, judging from the age).Originally Posted by Mark Gibney
* - With all due respect, this reference alone makes me think you should consult an electrician.
If it is operational as-is, best advice may be to leave it alone...?? Regardless, please be careful.
Last edited by Malcolm McLeod; 09-07-2022 at 3:52 PM. Reason: as-is?
Contributor
A magnetic switch is a safety function. If you are using the saw when the power goes out, it will not disconnect the switch. When power comes back on, the saw automatically starts again and creates a safety hazard. I think a magnetic switch is required by OSHA regulations for saw type machines in a commercial environment.
[OP]
Contributor
Thanks for the advice Malcolm - yes Square D, not Double. When it's pre-coffee early in the morning, or late, my brain tends to scramble words.
I understand all of what you're saying, it's what I figured to be the case. Many of my machines have magnetic starters, some don't. Probably the machine with the most potential for a dangerous surprise start, the table mounted router, does not have one.
Contributor
Here's a 3-phase magnetic switch you can get. Then take that Square D and manual front switch out of the mix complete.
https://www.amazon.com/Big-Horn-1883...WI6/ref=sr_1_7
Contributor
The SQ D starter looks like a manual starter not magnetic, does the start button remain down when pressed? If yes, it's a manual starter. Another question do you have 208V,240V,480V 3Ø power? If not how will it be powered? RPC, VFD, new motor?
Member
I'll take you at your word, so that leaves me guessing what is in both the big box and the little one. Big box looks too small to have a control power transformer AND the starter, so guessing just the starter with a 240VAC coil?
In addition to the anti-restart-on-power-recovery feature, mag starters offer the relatively easy option of placing multiple small start/stop and/or e-stop operators anywhere they are convenient. And leaving the 'big' mag starter in some equally convenient out-of-the-way spot.
So options:
1. Leave as-is and hope that the toggle doesn't melt or catch on a belt loop - and that I'm wrong about its ratings.
2.If big box is a mag starter (see Mr. Meyers' question), and the little box holds what I think it does - a dinky, 1-pole, off-spec toggle switch - but you really like the 'up front' location, then replace the switch with a proper industrial operator - i.e. 30.5mm SqD pull-to-start, push-to-stop pushbutton (PB) operator (figure ~$100-$120 for this quality). Keep the mag starter, and wire the new PB in parallel to the old built-in Start/Stop PBs on the starter box. The new PB should be a drop in replacement for the old toggle - just need a new cover? Both new & old PBs will carry 2 legs of power = 240VAC to the coil. The new push-pull PB will give you up-front convenience and (nearly) the safety of an e-stop.
3. You can get a 3ph 240V 1Hp manual starter with overloads and PB start/stop operators. I think size 0 (zero) will do - - $150-$300??I haven't needed one this small in 2 or eleven-teen years. It will look remarkably like the existing SqD box. Replace the whole existing electrical schmeer, including the toggle, with the new box - located in a suitably convenient spot for its size and in arm's reach.
Hope this helps.
Member
I can't fathom what the toggle would do if the SqD is a manual starter..??? Surely the previous owner didn't drop a phase to stop it?
Or, the toggle is 3-pole, 5A, 240V...? I've never seen such, but then haven't looked either.
ETA - I was looking at pics on my phone, now on PC, and maybe that isn't your typical doorbell-domelight toggle switch. Inquiring minds want to know.
Last edited by Malcolm McLeod; 09-07-2022 at 6:04 PM.
[OP]
Contributor
Here's that toggle switch -
IMG_5081.jpg
And here the dusty insides of the Sq D box - the second photo says it's a Square D Class 2510 Type B02 Class A.
IMG_5041.jpg IMG_5083.jpg I'll put a cord to the switch and see how it performs.
Aaron, the magnetic switch you linked to is great, I have two of them on machines already. Work great. Thanks.
Contributor
How would you turn off power to the machine if you wanted to work on the switchgear? I have a feeling having the extra switches or disconnects, is about meeting NEC/OSHA rules for a hard wired machine with no plug to pull.
Bill D
Contributor
It is a manual starter, if it was a mag starter there would not be "RESET" on the stop button, a reset on a mag starter is a separate button.
Member
Clearly, and color me... pink!?I got worried when I saw a close up of the 'toggle'.
Mr. Gibney, my horse turd receiving room will be open shortly. Send it.
That Class 2510 B02 manual starter is still made (looks only a tweek different), and it does have integral overload protection. If you do remove the starter, you will likely want to protect the motor using a properly sized CB or fuses. Sounds like you may have read the threads regarding protecting the device vs the wire - and how that applies here, so will move on.
So, on re-reading thru this all you could remove the SqD starter, and just use the toggle. I wouldn't - at least for me:
1) I don't care for the possible inadvertent activation (a sleeve or belt loop); would rather a push/pull or even 2-pos Off/On (twist);
2) I'd want the ability to run other higher or lower amperage equipment on this plug. Sizing a CB or fuses just for this makes that tough. YMMV.
...get a lockout for the CB, or a locking fused disconnect dedicated to this (hardwired) machine? My feeling is neither switch is lockable as-is, so likely its as simple as the operator didn't like reaching for the lower SqD buttons, so to speed things up they series-ed in the toggle up front? ...Maybe OEM?
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