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Eric Schmid
01-01-2022, 1:34 PM
I am switching the voltage on this 1.5HP table saw motor from 120V to 240V and would appreciate a second opinion on my understanding of this diagram. The motor is running in reverse rotation on this saw as the motor was wired with motor leads 5 & 8 reversed from 120V diagram.

So, I am planning on connecting one line voltage wire (black) to motor leads 2,4,8 (8 due to reverse rotation), and the second line wire (black) to motor lead 1. Motor leads 2,3,5 would then be connected together, but not connected to line voltage (power source).

Am I reading this correctly?

Also, I am going to be replacing the old light switch with a safety switch. This is on a table saw. Any recommendations for a fence rail mounted safety switch? I’d prefer a dual voltage switch, but 240V only would be fine as well. The main problem with the ones I’m finding, according to reviews, seems to be the incompatibility with readily available junction boxes. Is there a recommended model that has it’s own junction box?

Dan Friedrichs
01-01-2022, 2:29 PM
Is there a reason you're switching to 240V? It will not change the performance of the saw, at all, provided that your 120V circuit was adequately sized for a 15A load.

But if you want to rewire to 240V, I think you have a few errors. The diagram is not clear, but both line voltage connections are supposed to be to the wires going "down" to the bottom of the yellow boxes in the diagrams.

So 120V forward rotation, L1 goes to 1,3,8 and L2 goes to 4,5,2. Flip 5 and 8 to reverse.
For 240V forward rotation, L1 goes to 1, L2 goes to 4 and 5, and 3,8, and 2 are connected together (but to nothing else). Flip 5 and 8 to reverse.

For safety switch, are you thinking something like this? https://www.amazon.com/Woodstock-D4159-220-Volt-Paddle-Switch/dp/B005W17HSA/
If so, there are electrical boxes that readily fit it: https://www.menards.com/main/electrical/electrical-boxes-covers/electrical-boxes/sigma-electric-reg-1-gang-1-2-5-hole-weatherproof-gray-electrical-outlet-box/14251-5m/p-1444430910861-c-6425.htm?tid=-6742945865326664987&ipos=16

Eric Schmid
01-01-2022, 3:37 PM
Dan, thanks for your response. I wrote it wrong, but I have the same understanding. The second line connects to 4 & 5 or 4 & 8 depending on rotation.

Not looking for an improvement in performance by going from 120-240V. Reduction in amperage doesn’t hurt and I have the plug configurations for 240V available. The 40+ year old wire insulation in the SO cable running between the switch & motor have seen better days and the saw has been begging for a safety switch for years. While I’m there, might as well reduce amperage.

That is basically the type of switch I am looking for. In reading reviews of these switches, it seems some people are having trouble fitting them into standard 2 gang boxes. Could be user error, so I wanted to see if anyone here had success with a particular brand/model.

Ron Selzer
01-01-2022, 9:23 PM
here is a switch (https://www.grizzly.com/products/woodstock-220v-240v-paddle-switch/d4159) from Grizzly
the wiring needs to be
line to 1
line to 4,8
3,5,2
Ron