Inspect Water Piping; Check Optional Pumpout Compressor Water Piping; Check Relief Devices; Inspect Wiring - Carrier 17 Start Up & Operation Manual

Inspect Water Piping —
vided in the certified drawings, and the piping instructions
in the 17/19EX Installation Instructions manual. Inspect the
piping to the cooler and condenser. Be sure that flow direc-
tions are correct and that all piping specifications have been
met.
Piping systems must be properly vented, with no stress on
waterbox nozzles and covers. Water flows through the cooler
and condenser must meet job requirements. Measure the pres-
sure drop across cooler and across condenser.
Water must be within design limits, clean, and treated
to ensure proper machine performance and reduce the
potential of tubing damage due to corrosion, scaling, or
erosion. Carrier assumes no responsibility for chiller dam-
age resulting from untreated or improperly treated
water.
Check Optional Pumpout Compressor Water Pip-
ing —
If the optional storage tank and/or pumpout system
are installed, check to ensure the pumpout condenser water
has been piped in. Check for field-supplied shutoff valves
and controls as specified in the job data. Check for refrig-
erant leaks on field-installed piping.
Check Relief Devices —
have been piped to the outdoors in compliance with the lat-
est edition of ANSI/ASHRAE Standard 15 and applicable
local safety codes. Piping connections must allow for access
to the valve mechanism for periodic inspection and leak
testing.
Relief valves are set to relieve at the 225 psig (1551 kPa)
machine design pressure.

Inspect Wiring

Do not check voltage supply without proper equipment
and precautions. Serious injury may result. Follow power
company recommendations.
Do not apply any kind of test voltage, even for a rota-
tion check, if the machine is under a dehydration vacuum.
Insulation breakdown and serious damage may result.
1. Examine wiring for conformance to job wiring dia-
grams and to all applicable electrical codes.
2. On low-voltage compressors (600 v or less) connect
voltmeter across the power wires to the compressor starter
and measure the voltage. Compare this reading
with the voltage rating on the compressor and starter
nameplates.
3. Compare the ampere rating on the starter nameplate with
the compressor nameplate. The overload trip amps must
be 108% to 120% of the rated load amps.
4. The starter for a centrifugal compressor motor must con-
tain the components and terminals required for PIC re-
frigeration control. Check certified drawings.
5. Check the voltage to the following components and com-
pare to the nameplate values: oil pump contact, pump-
out compressor starter, and power panel.
6. Be sure that fused disconnects or circuit breakers have
been supplied for the oil pump, power panel, and pump-
out unit.
Refer to piping diagrams pro-
Be sure that relief devices
7. Check that all electrical equipment and controls are prop-
erly grounded in accordance with job drawings, certi-
fied drawings, and all applicable electrical codes.
8. Make sure that the customer's contractor has verified
proper operation of the pumps, cooling tower fans, and
associated auxiliary equipment. This includes ensuring
that motors are properly lubricated and have proper elec-
trical supply and proper rotation.
9. Tighten up all wiring connections to the plugs on the
SMM, 8-input, and PSIO modules.
10. Ensure that the voltage selector switch inside the power
panel is switched to the incoming voltage rating.
11. On machines with free-standing starters, inspect the power
panel to ensure that the contractor has fed the wires into
the bottom of the panel. Wiring into the top of the panel
can cause debris to fall into the contactors. Clean and
inspect the contactors if this has occurred.
Voltage to terminals LL1 and LL2 comes from a con-
trol transformer in a starter built to Carrier specifica-
tions. Do not connect an outside source of control power
to the compressor motor starter (terminals LL1 and LL2).
An outside power source will produce dangerous volt-
age at the line side of the starter, because supplying volt-
age at the transformer secondary terminals produces in-
put level voltage at the transformer primary terminals.
CHECK INSULATION RESISTANCE (HERMETIC MO-
TOR) — Test the machine compressor motor and its power
lead insulation resistance with a 500-v insulation tester such
as a megohmmeter. (Use a 5000-v tester for motors rated
over 600 v.) Factory-mounted starters do not require a
megohm test.
1. Open the starter main disconnect switch and follow lockout/
tagout rules.
If the motor starter is a solid-state starter, the motor
leads must be disconnected from the starter before
an insulation test is performed. The voltage gener-
ated from the tester can damage the starter solid-
state components.
2. With the tester connected to the motor leads, take
10-second and 60-second megohm readings as follows:
6-Lead Motor — Tie all 6 leads together and test be-
tween the lead group and ground. Next tie leads in pairs,
1 and 4, 2 and 5, and 3 and 6. Test between each pair
while grounding the third pair.
3-Lead Motor — Tie terminals 1, 2, and 3 together and
test between the group and ground.
3. Divide the 60-second resistance reading by the
10-second reading. The ratio, or polarization index, must
be one or higher. Both the 10- and 60-second readings
must be at least 50 megohms.
If the readings on a field-installed starter are unsatisfac-
tory, repeat the test at the motor with the power leads dis-
connected. Satisfactory readings in this second test indi-
cate the fault is in the power leads.
NOTE: Unit-mounted starters do not have to be meg-
ohm tested.
CHECK INSULATION RESISTANCE (OPEN-DRIVE
MOTOR) — Before operating voltages is applied to the mo-
tor, whether for checking rotation direction or for actual op-
eration, the resistance of the stator winding insulation should
be measured.
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