S-17A Resistance Check; S-15B Capacitance Check; S-16A Checking Fan And Blower Motor Windings (Psc Motors) - Daikin DP14UM Service Instructions Manual

SERVICING
Relay, Start
A potential or voltage type relay is used to take the start
capacitor out of the circuit once the motor comes up
to speed. This type of relay is position sensitive. The
normally closed contacts are wired in series with the start
capacitor and the relay holding coil is wired parallel with
the start winding. As the motor starts and comes up to
speed, the increase in voltage across the start winding will
energize the start relay holding coil and open the contacts
to the start capacitor.
Two quick ways to test a capacitor are a resistance and a
capacitance check.

S-17A Resistance Check

High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be
present. Failure to do so may cause property
damage, personal injury or death.
1. Discharge capacitor and remove wire leads.
Discharge capacitor through a 20 to 30 OHM resistor
before handling.
Testing Capacitor Resistance
14
WARNING
WARNING
2. Set an ohmmeter on its highest ohm scale and
connect the leads to the capacitor -
A. Good Condition - indicator swings to zero and
slowly returns to infinity. (Start capacitor with
bleed resistor will not return to infinity. It will
still read the resistance of the resistor).
B. Shorted - indicator swings to zero and stops
there -replace.
C. Open - no reading - replace. (Start capacitor
would read resistor resistance.)

S-15B Capacitance Check

Discharge capacitor through a 20 to 30 OHM resistor
before handling.
Using a hookup as shown below, take the amperage and
voltage readings and use them in the formula:
Capacitance (MFD) =
Testing Capacitance
S-16A Checking Fan And Blower Motor Windings
(Psc Motors)
The auto reset fan motor overload is designed to protect
the motor against high temperature and high amperage
conditions by breaking the common circuit within the
motor, similar to the compressor internal overload.
However, heat generated within the motor is faster to
dissipate than the compressor, allow at least 45 minutes
for the overload to reset, then retest.
WARNING
2650 X Amperage
Voltage