The test voltage, based on the motor operating voltage, is
as follows:
Operating Voltage
DC Test Voltage
0-
900
500
901- 7000
1000
7001-14500
2500
This is particularly important if the motor may have been
exposed to excessive dampness either during transit or while
in storage. A ‘‘megger’’ type instrument can be used to mea-
sure the insulation resistance. The test voltage should be ap-
plied between the entire winding (all winding leads connected
together) and ground for approximately one minute with the
winding at ambient temperature. The recommended mini-
mum insulation resistance is determined as follows:
RM =
KV + 1
Where
RM =
Recommended minimum insulation resis-
tance in megohms at 104° F (40° C) of the
entire winding.
KV =
Rated motor terminal to terminal voltage in
kilovolts (1000 volts = 1 KV).
On a new winding, where the contaminant causing low
insulation resistance is generally moisture, drying the wind-
ing through the proper application of heat will normally in-
crease the insulation resistance to an acceptable level. The
following are several accepted methods for applying heat to
a winding:
1. If the motor is equipped with space heaters, they can be
energized to heat the winding.
2. Direct current (as from a welder) can be passed through
the winding. The total current should not exceed approxi-
mately 50% of rated full load current. If the motor has
only 3 leads, 2 must be connected together to form one
circuit through the winding. In this case, one phase will
carry the full applied current and each of the others, one-
half each. If the motor has 6 leads (3 mains and 3 neu-
trals), the 3 phases should be connected into one series
circuit.
3. Heated air can be either blown directly into the motor or
into a temporary enclosure surrounding the motor. The
source of heated air should preferably be electrical as op-
posed to fueled (such as kerosene) where a malfunction
of the fuel burner could result in carbon entering the mo-
tor. Caution must be exercised, when heating the motor
with any source of heat other than self contained space
heaters, to raise the winding temperature at a gradual rate
to allow any entrapped moisture to vaporize and escape
without rupturing the insulation. The entire heating cycle
should extend over 15 to 20 hours.
Insulation resistance measurements can be made while the
winding is being heated. However, they must be corrected to
104 F (40 C) for evaluation since the actual insulation re-
sistance will decrease with increasing temperature. As an ap-
proximation for a new winding, the insulation resistance will
approximately halve for each 18° F (10° C) increase in in-
sulation temperature above the dew point temperature.
Open-Drive Motor Pre-Start Checks
— To pre-
vent damage to the motor, the following steps must be taken
prior to initial start-up:
1. Remove the shaft shipping brace (if supplied).
2. For sleeve bearing motors, the oil reservoir must be filled
with oil to the correct level. The proper oil is a rust and
oxidation inhibited, turbine grade oil. The viscosity of the
oil must be 32 ISO (150 SSU) at 100 F (37.7 C). Oil ca-
pacity in each of the two bearings is 0.6 gal. (2.3 L) per
bearing. Use of Carrier Oil Specification PP16-0 is ap-
proved (Mobil DTE Light or Sun Oil SUNVIS 916).
3. If possible, the shaft should be turned over by hand to
ensure that there is free rotation. On sleeve bearing mo-
tors, the shaft should be moved to both extremes of its
end play while it is being rotated, and the oil rings should
be viewed through the viewing ports in the top of the bear-
ing housing to verify free ring rotation.
4. On fan-cooled motors, the area around he external fan
inlet should be checked for loose debris that could be drawn
into the fan during operation.
5. All external, factory-made, bolted joints should be checked
for any looseness that may have occurred in transit. Refer
to Table 6 for recommended bolt torques.
Table 6 — Recommended Torque
Bolt size
1
⁄
4
(
5
⁄
16
(
3
⁄
8
(
1
⁄
2
(
5
⁄
8
(
3
⁄
4
(
7
⁄
8
(
1
(
1
1
⁄
3
(
1
1
⁄
2
(
Grade
SAE GR 5
Torque*
Ft-lbs
3.5
7
12
31
63
115 180 275
550
960
N.m
4.7
9.5
16
42
85
156 244 373
746
1302
Bolt size
M4
M6
M8
M10
M12
M10
M12
M16
Grade
DIN 8.8
DIN 12.9
Torque*
Ft-lbs
2
8
15
35
65
45
92
225
N.m
2.7
11
20
47
88
61
125
305
*Torque values based upon dry friction.
Carrier Comfort Network Interface —
The Carrier
Comfort Network (CCN) communication bus wiring is sup-
plied and installed by the electrical contractor. It consists of
shielded, 3-conductor cable with drain wire.
The system elements are connected to the communication
bus in a daisy chain arrangement. The positive pin of each
system element communication connector must be wired to
the positive pins of the system element on either side of it;
the negative pins must be wired to the negative pins; the sig-
nal ground pins must be wired to signal ground pins.
To attach the CCN communication bus wiring, refer to
the certified drawings and wiring diagrams. The wire is in-
serted into the CCN communications plug (COMM1) on the
PSIO module. This plug also is referred to as J5.
NOTE: Conductors and drain wire must be 20 AWG (Ameri-
can Wire Gage) minimum stranded, tinned copper. Indi-
vidual conductors must be insulated with PVC, PVC/nylon,
vinyl, Teflon, or polyethylene. An aluminum/polyester 100%
foil shield and an outer jacket of PVC, PVC/nylon, chrome
vinyl or Teflon with a minimum operating temperature range
of –20 C to 60 C is required. See table below for cables that
meet the requirements.
53
Summary of Contents for 17
Page 13: ...Fig 6 Open Drive 17 Series Lubrication Cycle 13 ...
Page 15: ...Fig 7 17EX Controls and Sensor Locations 15 ...
Page 16: ...Fig 7 17EX Controls and Sensor Locations cont 16 ...
Page 17: ...Fig 7 17EX Controls and Sensor Locations cont 17 ...
Page 19: ...Fig 8 19EX Controls and Sensor Locations cont 19 ...
Page 23: ...Fig 16 17 19EX LID Menu Structure 23 ...
Page 24: ...Fig 17 17 19EX Service Menu Structure 24 ...
