Winding Resistance (Line-To-Line); Resistance Charts - Grundfos UP XL Serie Instrucciones De Instalación Y Funcionamiento

Evaluation
The resistance values for new motors must
exceed 1,000,000 ohms. If they do not, replace
power head.

6.5 Winding resistance (line-to-line)

To check the winding resistance of the motor
windings, use a megohmmeter and follow these
steps.
1. Turn the POWER OFF.
2. Disconnect all electrical leads to the motor.
3. Set the scale selector on the
megohmmeter to R x 1, touch its leads
together and adjust the indicator to zero.
4. Using the charts in section 5.6 for
reference, touch the leads of the
megohmmeter to the appropriate pair of
connectors. Check all pairs that are present
and write down and label (RA
readings.
– In T-box at L & N: UP will = Speed 3/High
– In T-box at L & N: UPS value depends on
the selected speed (Speed 1, 2, or 3)
– For both UP and UPS: with the terminal
box removed, check all combinations RA,
S , S
1 2
5. Compare your readings to the matching
model, phase and voltage listed in the charts
in section 5.6.
Evaluation
The resistance values must fall within the
tolerances listed in section 5.6. If they do not,
replace the power head.

6.6 Resistance charts

Checking connections in the terminal box at the
power connections L and N; see fig. 14 for 115 V
and 208 - 230 V.
Connection
L to N (Speed 3)
115V L to N (Speed 2)
L to N (Speed 1)
Connection
L to N (Speed 3)
208V
- L to N (Speed 2)
230V
L to N (Speed 1)
*T can only be checked with the terminal box
removed; if the thermiks is open the pump will
not run.
, RS , RS ) all
1 1 2
OHM value
Nominal
range
6.9 to
= 7.55
8.01
9.7 to
= 10.54
11.38
12.97 to
= 14.10
15.23
OHM value
Nominal
range
34.63 to
= 37.65
40.66
41.57 to
= 45.19
48.81
56.67 to
= 61.60
66.53
L N
Fig. 14
Checking at the pin connection behind the
terminal box (see section 6.3 Replacing the
terminal box or capacitor for terminal box
removal):
Stator
pin connection
1 to 2
4 to 5
6 to 7
2 to 8
Connection
RA (1 to 2)
RS (4 to 5)
1
115V
RS (6 to 7)
2
T (2 to 8)
Connection
RA (1 to 2)
208V
RS (4 to 5)
1
-
RS (6 to 7)
230V
2
T (2 to 8)
Fig. 15 shows terminal plug-in stator relationship
to the top / nameplate end of the stator.
Fig. 15 Terminal plug in stator
Fig. 16 Internal wiring
Winding groups
RA: Main winding
RS : Auxiliary winding
1
RS : Auxiliary winding
2
T: Thermiks
OHM value Nomin
range al
= 6.7 to 7.9 7.3
= 3.0 to 3.6 3.3
3.0 to 3.6 3.3
= 0
OHM value Nomin
range al
= 30.4 to 35.6 33
= 12.0 to 14.0 13
= 12.0 to 14.0 13
= 0
13