Centroid Community CNC Support Forum

Hi,
I'm working on my Bridgeport S2I2 upgrade and found my contactors are all 110vac coils - so I'm planning on using 110vac on the E-Stop and Flood Pump coil circuits. I do have a few questions:

1. From what I can read it appears the AllinOne is rated for the 110vac E-Stop and Flood pump circuit on the relays - please confirm.

2. I would like to add the quencharcs to the 2 contactors and 1 to the Lube pump. Is the Ajax quencharc ok for these three applications (all three 110vac) or do I need something different. There doesn't seem to be any old ones lying about.

3. Is the Pendant E-Stop Button, and the 2nd E-Stop button also rated for 110vac?

4. Somewhere here on the board I read about Single Phase Flood pump contactors not needing overload protection - is that right - it seems to me it would still be a good idea - unless there's something about the overload protection on the contactors that require all three legs powered. Though my contactor overload is bi-metal.

Thanks

Jay

Jay,

1. The relays on the ALLIN1DC are rated @ 5A 30 VDC or 10A 240VAC. They will be fine for your 110VAC

2. The Quencharcs will work.

3. Yes

4. Overload protection is always a good idea.

Yes, you should always install appropriately-rated overload protection for motor loads.

This is best done with a 3-pole contactor and overload assembly.

If your overload unit has "single phase sensitivity", meaning that it will trip in the event that one (or two) of the three phases is not carrying current, then you will need to loop one of the two power leads back around, so it passes through the contactor/overload assembly twice.

For example, leg 1 would go in L1, out T1 directly to the motor; leg 2 would go in L2; a jumper would loop around from T2 to L3; and then power would go out T3 to the motor.

If you are using Schneider / Telemecanique / SquareD components, "LRD..." overload relays have single phase sensitivity, and require a loop-back-through with single-phase motors; while "LR3D..." overload relays do not have single phase sensitivity, and can be used with just two poles loaded.