Checking Compressor Windings; S-17A Resistance Test - Daikin DRG0361DL00001S Service Instructions Manual

SERVICING
S-17 Checking Compressor Windings
WARNING
Hermetic compressor electrical terminal venting can
be dangerous. When insulating material which
supports a hermetic compressor or electrical terminal
suddenly disintegrates due to physical abuse or as a
result of an electrical short between the terminal and
the compressor housing, the terminal may be
expelled, venting the vapor and liquid contents of the
compressor housing and system.
If the compressor terminal PROTECTIVE COVER and gasket
(if required) are not properly in place and secured, there is
a remote possibility if a terminal vents, that the vaporous
and liquid discharge can be ignited, spouting flames
several feet, causing potentially severe or fatal injury to
anyone in its path.
This discharge can be ignited external to the compressor
if the terminal cover is not properly in place and if the
discharge impinges on a sufficient heat source.
Ignition of the discharge can also occur at the venting
terminal or inside the compressor, if there is sufficient
contaminant air present in the system and an electrical arc
occurs as the terminal vents.
Ignition cannot occur at the venting terminal without the
presence of contaminant air, and cannot occur externally
from the venting terminal without the presence of an
external ignition source.
Therefore, proper evacuation of a hermetic system is
essential at the time of manufacture and during servicing.
To reduce the possibility of external ignition, all open
flame, electrical power, and other heat sources should be
extinguished or turned off prior to servicing a system.
54

S-17A Resistance Test

Each compressor is equipped with an internal overload.
The line break internal overload senses both motor
amperage and winding temperature. High motor
temperature or amperage heats the disc causing it to
open, breaking the common circuit within the compressor
on single phase units.
Heat generated within the compressor shell, usually due to
recycling of the motor, high amperage or insufficient gas to
cool the motor, is slow to dissipate. Allow at least three to
four hours for it to cool and reset, then retest.
HIGH VOLTAGE!
Disconnect ALL power before servicing
or installing this unit. Multiple power
sources may be present. Failure to do so
may cause property damage, personal injury
or death.
1. Remove the leads from the compressor terminals.
See warnings S-17 before removing compressor
terminal cover.
2. Using an ohmmeter, test continuity between
terminals S-R, C-R, and C-S, on single phase units or
terminals T1, T2 and T3, on 3 phase units.
OHMMETER
Testing Compressor Windings
If either winding does not test continuous, replace the
compressor.
NOTE: If an open compressor is indicated, allow ample
time for the internal overload to reset before replacing
compressor.
C
R
S
COMP