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APPENDIX G — OPTIONAL MOTORMASTER
®
V CONTROL
TO RESET FACTORY DEFAULTS
To recognize a factory reset, the MMV controller must see a
change in P48.
1. Cycle power from Motormaster
®
V control.
2. Enter PROGRAM mode by entering password.
3. Scroll to P48 by using UP and DOWN buttons and then
press MODE. One of the 12 mode numbers will appear.
(Modes 1, 2 and 4 are used for these units.)
4. Restore factory defaults by changing the value in P48
using UP and DOWN buttons and then storing the value
by pressing MODE.
5. Press MODE again to re-display the value of P48.
6. Change the value of P48 to the desired factory default
mode (see Table Q) using UP and DOWN buttons then
press MODE. The Motormaster V control is now restored
to factory settings.
TROUBLESHOOTING
Troubleshooting the Motormaster V control requires a combina-
tion of observing system operation and VFD display information.
If the liquid line pressure is above the set point and the VFD is
running at full speed, this is a normal condition. The fan CAN-
NOT go any faster to maintain set point.
If the VFD is not slowing down even though liquid line pres-
sure is below set point, the VFD could be set for manual con-
trol or the control may be receiving faulty pressure transducer
output. Corrective action would include:
• Check that VDC signal between TB5 and TB2 is between
0.5 v and 4.5 v.
• Restore VFD to automatic control.
• Change parameter P05 back to correct value shown in
Table AR.
The MMV control also provides real time monitoring of key
inputs and outputs. The collective group is displayed through
parameters P50 to P56 and all values are read only. These val-
ues can be accessed without entering a password.
Press MODE twice and P50 will appear.
Press MODE again to display value.
• To scroll to P51-P56 from P50, use UP and DOWN but-
tons then press MODE to display the value.
• P50: FAULT HISTORY — Last 8 faults
• P51: SOFTWARE version
• P52: DC BUS VOLTAGE — in percent of nominal. Usu-
ally rated input voltage x 1.4
• P53: MOTOR VOLTAGE — in percent of rated output
voltage
• P54: LOAD — in percent of drives rated output current
• P55: VDC INPUT — in percent of maximum input:
100% will indicate full scale which is 5 v
• P56: 4-20 mA INPUT — in percent of maximum input.
20% = 4 mA, 100% = 20 mA
NOTE: The Motormaster V transducer is attached to circuit A. If
circuit A compressor power is interrupted (overload, high pressure
cutout, etc.) the outdoor fans will operate at a reduced speed re-
sulting from erroneous low pressure readings. This process may
cause a high pressure safety cutout on circuit B compressor. If
only circuit B is capable of operating for a temporary period of
time because of a circuit A problem, the transducer will have to be
moved to the circuit B service port until circuit A can be repaired.
Once the problem is repaired, move the transducer back to
circuit A for proper unit operation.
Fault Lockout
If a fault lockout (LC) has occurred, view the fault history in
P50 to find the last fault. Once P50 is displayed, use the arrow
buttons to scroll through the last 8 faults. Any current faults or
fault codes from the fault history can be analyzed using
Table AS.
TO DISABLE AUTOMATIC CONTROL MODE AND
ENTER MANUAL SPEED CONTROL:
1. Change P05 to ‘01- keypad’.
2. Push UP and DOWN arrow button to set manual speed.
3. Set P05 to proper value to restore automatic control
according to Table AR.
TO PROVIDE MANUAL START/STOP CONTROL
With power removed from VFD, remove start command jump-
er and install a switch between the appropriate start terminals
as required in Table AQ.
EPM Chip
The drive uses a electronic programming module (EPM) chip
to store the program parameters. This is an EEPROM memory
chip and is accessible from the front of the VFD. It should not
be removed with power applied to the VFD.
Loss of CCN Communications
Carrier Comfort Network
®
(CCN) communications with exter-
nal control systems can be affected by high frequency electri-
cal noise generated by the Motormaster
®
V control. Ensure
unit is well grounded to eliminate ground currents along com-
munication lines.
If communications are lost only while Motormaster V control
is in operation, order a signal isolator (CEAS420876-2) and
power supplies (CEAS221045-01, 2 required) for the CCN
communication line.
Liquid Line Pressure Set Point Adjustment
Adjusting the set point may be necessary to avoid interaction with
other head pressure control devices. If adjustment is necessary, use
the set point parameter found in P-34 for R-410A. A lower value
will result in a lower liquid line set point. As an example for R-
410A, decreasing the P-34 from 24 to 23 will decrease the liquid
line pressure by approximately 15 psig. It is recommended to ad-
just R-410A units by 1.
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