Carrier TRANSICOLD 69NT40-511-200, Операция и обслуживание

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6-28 T-294-01
6.26 POWER FACTOR CORRECTOR
CAPACITORS (PFC)
The power factor corrector capacitors are of the
permanent-split capacitor type. There are a total of three
capacitors with discharge resistors enclosed in a single
case.
a. When to check for a defective capacitor
The capacitors assist in correcting current draw by the
compressor. If one or more of the capacitors is faulty,
there will be an imbalance in current. In addition, the
power consumption of the unit will increase.
b. Removing the capacitor
WARNING
Make sure power to the unit is OFF and
power plug disconnected before removing
capacitor(s).
WARNING
Before removing the capacitors the
terminals must be checked for voltage with a
multimeter. The discharge resistors
installed on the unit (capacitors) should
bring the voltage to a safe level in a minute.
However, there may be a broken resistor
that retains voltage for a longer period, it is
highly recommended to wait 15 minutes and
to check for voltage.
1. The capacitors are located on the unit sidewall
above the evaporator fan deck, and may be removed
by two methods:
(a.) If container is empty , open upper rear panel of
the unit. The capacitors will be on the right and
may be serviced after disconnecting power
plug.
(b.) If container is full, turn the unit power OFF and
disconnect power plug. Remove the upper fresh
air makeup vent (see Figure 2-1).
WARNING
With power OFF discharge the capacitor
and disconnect the circuit wiring.
c. Checking the capacitor
If the capacitor is suspected of malfunction, you may
choose to simply replace it. Direct replacement requires
a capacitor of the same value. Two methods for
checking capacitor function are:
1. Volt-ohmmeter set on RX 10,000 ohms.
Connect ohmmeter leads across the capacitor terminals
and observe the meter needle. If the capacitor is good,
the needle will make a rapid swing toward zero
resistance and then gradually swing back toward a very
high resistance reading. The reading should read about
330,000 ohms (for a good capacitor) due to the
discharge resistors.
If the capacitor has failed open, the ohmmeter needle
will not move when the meter probes touch the
terminals. If the capacitor is shorted, the needle will
swing to zero resistance position and stay there.
2. Capacitor analyzer:
The function of the analyzer is to read the microfarad
value of a capacitor and to detect insulation breakdown
under load conditions. The important advantages of a
analyzer are its ability to locate capacitors that have
failed to hold their microfarad ratings, or those that are
breaking down internally during operation. It is also
useful in identifying capacitors when their microfarad
rating marks have become unreadable.
6.27 CONTROLLER/DATACORDER
a. Handling of Controller/DataCORDER
These guidelines should be followed when handling the
Controller/DataCORDER module. These steps should
be implemented when replacing the module, when
doing
any arc welding on the unit, or when service to the
refrigeration unit requires handling and removal of the
Controller.
CAUTION
Remove Controller/DataCORDER module
and
unplug all connectors before
performing any arc welding on any part of
the container.
Do not remove wire harnesses from modules
unless you are grounded to the unit frame
with a static safe wrist strap.
1. Obtain a grounding wrist strap and a static
dissipation mat. The wrist strap, when properly
grounded, will dissipate any potential buildup on
the body. The dissipation mat will provide a
static-free work surface on which to place and/or
service the Controller/DataCORDER module.
NOTE
Use a dissipation mat, order CTD P/N
07-00277-00.
2. Disconnect and secure power to the unit.
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