Cable Resistance – Copper - Xylem Goulds CentriPro Series Service Manual

1. Set the scale lever to R x 1 for values under 10 ohms.
For values over 10 ohms, set the scale lever to R x 10.
Zero balance the ohmmeter as described earlier.
!
WARNING!
Open master breaker and disconnect all
leads from starter to avoid damage to meter
or electric shock hazard. Connect the ohm-
meter leads as shown below.
2. Connect the ohmmeter leads as shown below.
Cable Resistance – Copper
Size
Cable
14
12
10
8
6
4
RX100K
2
0
Drop
Cable
00
With
Ground
000
Wire
0000
See motor data pages for motor resistance ratings.
What it Means
1. If all ohm values are normal, the motor windings are
neither shorted nor open, and the cable colors are
correct.
2. If any one ohm value is less than normal, the motor is
shorted.
3. If any one ohm value is greater than normal, the winding
or the cable is open or there is a poor cable joint or
connection.
4. If some ohm values are greater than normal and some
less, the leads are mixed.
38
Paired Wire
Resistance
(ohms per foot)
.0050
.0032
.0020
O H M S
.0013
.0008
Z E R O
O H M S
.0005
R X 1 0 0 R X 1 0 0 0
R X 1 0 R X 1 0 K
R X 1 R X 1 0 0 K
.0003
.0002
.00015
.00013
.00010
If aluminum cable is used the
readings will be higher. Divide
the ohm readings on this chart
by 0.61 to determine the actual
resistance of aluminum cable.
Ground
Wire
Motor
Leads
O H M S
Z E R O
O H M S
R X 1 0 0 R X 1 0 0 0
R X 1 0 R X 1 0 K
R X 1 R X 1 0 0 K
RX1
or
RX10