Filter Drier; Replacing Switch; Moisture/Liquid Indicator; Motormaster V Controls - Carrier 38APS025 Manual

This is a required field supplied and in-
Filter Drier —
stalled device. Replace whenever the moisture/liquid indicator
shows moisture in the system.
High Pressure Switch —
with one high pressure switch per circuit, for high pressure pro-
tection. The high pressure switch is an automatic reset device.
For pressure settings, see High Pressure Switch (HPS) on
page 28. See Fig. 33-43 for typical locations of the high pres-
sure switch on each circuit.

REPLACING SWITCH

WARNING
Care should be exercised while removing high pressure
switch. Refrigerant system is under pressure. DO NOT
remove high pressure switch before the condensing unit
has been isolated and the refrigerant has been removed
using standard refrigeration practices. Be sure to use proper
personal protection equipment to guard against accidental
exposure to refrigerant.
The high pressure switch is mounted on a female flare fit-
ting. There is no Schrader valve under the high pressure switch.
If the high pressure switch must be removed, the condensing
unit must be isolated and the refrigerant removed using stan-
dard refrigeration practices before removing the high pressure
switch, using a back-up wrench to secure the fitting. Be sure to
loop cable and secure with a wire tie to create a strain relief as
shown in Fig. 48 on page 40.
Moisture/Liquid Indicator —
supplied and installed device. A clear flow of liquid refrigerant
indicates sufficient charge in the system. Bubbles indicate un-
dercharged system or the presence of non-condensables. Mois-
ture in the system measured in parts per million (ppm) changes
the color of the indicator. See the specific manufacturer's in-
structions for moisture indication. Change the filter driers at the
first sign of moisture in the system.
IMPORTANT: Unit must be in operation at least 12
hours before moisture indicator can give an accurate
reading. With unit running, indicating element must be
in contact with liquid refrigerant to give a true reading.
Motormaster ® V Controls —
troller is properly configured, powered, has a control signal,
and has the Run jumper closed, the controlled fan motor should
be operating. The Motormaster V controller has internal diag-
nostics that are available on the device. The default display is
the frequency command for the drive. If the drive is in a stop
state, the display will indicate "---". If the drive is commanded
to start, the display will indicate the commanded frequency.
The motor speed may lag the commanded speed until the mo-
tor's actual speed reaches the commanded speed.
WARNING
The opening of a branch-circuit protective device may be
an indication that a fault has been interrupted. To reduce
the risk of fire or electric shock, current carrying parts and
other components of the controller should be examined and
replaced if damaged.
815
All 38AP units are equipped
This is a required field
If the Motormaster con-
TROUBLESHOOTING — The drive is programmed to re-
start automatically after a fault and will attempt to restart three
times after most faults (the drive will not restart after CF, cF,
GF, F1, F2-F9, or Fo faults). If all three restart attempts are un-
successful, the drive will trip into FAULT LOCKOUT (LC),
which requires a manual reset. To do a manual reset, if the fault
condition has been removed, cycle power to the unit to reset
the VFD.
Troubleshooting the Motormaster V controller requires a
combination of observing system operation and VFD informa-
tion. The drive provides 2 kinds of troubleshooting modes: a
status matrix using the 3-digit display (Parameters P57, P58)
and real time monitoring of key inputs and outputs. The collec-
tive group is displayed through parameters P50 through P60.
All values are read-only. These parameters can be accessed
without a password. Pressing the Mode button twice will
change the display to P50. Use the up and down arrow buttons
to reach the desired parameter. Press the Mode button to view
the parameter value. The upper right decimal point will blink
indicating the parameter value. See Table 71 for a list of trou-
bleshooting parameters.
Fault Codes — Motormaster V fault codes will be displayed
in parameter P50. Up to 8 faults will be displayed in a 3-digit
format. The first digit is the alarm occurrence, 1 through 8. The
next 2 digits are the fault code. See Fig. 182 for an example of
the fault code. Faults are stored from most recent to oldest. Ta-
ble 72 lists Motormaster fault codes.
FAULT NO.
(1-8)
Fig. 182 — Motormaster V
P50 Fault Code Display
Manual Control — The Motormaster V controller can be con-
figured for manual control to allow the user to control the mo-
tor speed to test its operation. To disable automatic control
mode and enter manual speed control mode follow the instruc-
tions in the section Motormaster V Drive Configuration on
page 126 to obtain access to the parameter mode. Change the
following parameter:
1. Change parameter P05 to 01. This will allow for manual
speed control.
2. With the Run jumper closed, push the up and down arrow
buttons to set manual speed of the controlled motor.
3. Be sure to set P05 back to 04 to restore 4 to 20 mA con-
trol once the test is complete.
152
2-DIGIT FAULT CODE
(SF IN THIS EXAMPLE)
a38-7451