Correcting phase polarity – Southbend SB1046PF User Manual
Page 94
-92-
For Machines Mfg. Since 3/11
Turn-Nado
®
Gearhead Lathes
E L E C T R I C A L
Correcting Phase
Polarity
This sub-section is only provided for
troubleshooting. If you discover during the test
run that the lathe will not operate, or that the
spindle runs backwards, the lathe may be wired
out of phase.
Without the proper test equipment to determine
the phase of power source legs, wiring machinery
to 3-phase power may require trial-and-error.
Correcting this is simply a matter of reversing
the positions where two of the incoming power
source wires are connected.
To correct wiring that is out of phase:
1. Push the STOP button, turn the master
power switch to OFF, and disconnect the
machine from power.
2. Open the electrical box and swap any two
hot wires coming from the power supply, as
illustrated in Figure 137.
3. Close and latch the electrical box, and
reconnect the machine to the power source.
Swap any two
of these wires
L3
L2
L1
To Power
Supply
Hot
MASTER
POWER SWITCH
Hot
Hot
Ground
Figure 137. Swapping L1 and L2 power connections to
correct out-of-phase wiring.