Wye-Delta Vs Across-The-Line (Xl); Starting Option; Capacity Control - Carrier ComfortLink 6 Series Controls, Start-Up, Operation, Service, And Troubleshooting

Table 4 — Comfort Link™ Compressor Protection
(CCP) Board Plug Connections
CCP PLUG
J1 24-vac Power Input
J2, J6 Compressor Contactor(s)
High Pressure Switch, Oil and Motor Cooling
J3, J7
Solenoids
J4, J8 Current Sensor Input
J5, J9 Compressor Motor Temperature Input
J10, J11 Communication Connections
NOTE: Plugs J2-J5 are for compressors A1 (CCP1) or A2 (CCP2).
Plugs J6-J9 are for compressor B1 (CCP1) or B2 (CCP2).
Table 5 — CCP Address DIP Switch Settings
CCP1
UNIT
1 2
30GXN,R080-178 L OFF
30HXA076-186
30HXC076-186
30GXN,R204-350 L OFF
30HXA206-271
30HXC206-271
To verify proper must trip amps header configuration, use
the Navigator and the Configuration mode portion of Appendix
A to locate the items CM.A1, CM.A2, CM.B1 and CM.B2 in
the UNIT sub-mode. See Appendix A for correct settings. If
the values do not match those in Appendix A, verify that the
configuration headers have been properly punched out.
The CCP communicates on the LEN (Local Equipment
Network) bus to the MBB. Proper operation of the CCP board
can be verified by observing the 2 LEDs located on the board.
The red LED blinks at a rate of once every 1 to 2 seconds. This
indicates that the module is powered and operating correctly.
The green LED blinks when the module is satisfactorily com-
municating with the MBB. The CCP communicates status of
its inputs and outputs and reports 13 different alarm conditions
to the MBB.
The CCP module has many features that are specifically
designed to protect the compressor, including reverse rota-
tion protection. Do not attempt to bypass or alter any of the
factory wiring. Any compressor operation in the reverse
direction will result in a compressor failure that will require
compressor replacement.
The MBB will generate an alert when it receives an
alarm input from the CCP. The alert will be generated as T051,
T052, T055, or T056 (for Compressors A1, A2, B1,
B2 respectively). Press the
Navigator simultaneously to expand the full meaning of the
alert. For example, the Navigator will read: T055 CIRCUIT B,
COMPRESSOR 1 FAILURE-HIGH PRESSURE SWITCH
TRIP.
The high-pressure switch is wired in series with the relay
coils of the 8 relays on the CCP. If this switch opens during
operation, all relays on the CCP are deenergized and the com-
pressor is stopped. The failure is reported to the MBB and the
processor module locks off the compressor from restarting
until the alarm is manually reset.
Wye-Delta vs Across-the-Line (XL) Starting
Option —
All 30GXN,R and 30HX chillers operating at
voltages of 230-3-60, 208/230-3-60 or 230-3-50 (4, 5, or 8 at
DESCRIPTION
CCP2
3 4 1 2 3
0 0 — — — —
0 0 L OFF 1
and buttons on the
ENTER ESCAPE
Position 12 in model number) are supplied with factory-
installed Wye-Delta starters. All other voltage options can be
ordered with either Wye-Delta or XL starting options. The XL
starting method is the most cost effective and simply starts the
compressor motor in a Delta configuration (the motors are
designed for continuous operation in this configuration) using a
single contactor. See Fig. 5. This is the simplest starting meth-
od to use and is ideal where starting current does not require
limiting.
Where current limitations exist, the Wye-Delta option may
be used. See Fig. 6. This option uses a factory-installed starter
assembly for each compressor, which consists of 3 contactors
labelled 1M, 2M, and S. As the compressor is started, the CCP
module energizes contactors 1M and S, which connects and
energizes the motor windings in a Wye configuration. The
starting current required will be approximately 60% less than
that required for an XL start due to the higher impedance of the
4
motor windings when Wye connected. The compressor will
attain about 100% of its normal operating speed (approximate-
ly 3 to 5 seconds) before the CCP module deenergizes the S
contactor and energizes the 2M contactor, switching the com-
1
pressor windings to a Delta wiring configuration. The S and
2M contactors in the starter assembly are both mechanically
and electrically interlocked so that they will not both be ener-
gized at the same time.
Do not alter the factory-installed power wiring from the
control box terminal block to the compressor junction block.
Doing so will cause permanent damage to the compressor and
will require that the compressor be replaced.
Capacity Control —
pressors, loaders, and minimum load control valves to maintain
the user-configured leaving chilled fluid temperature set point.
Entering fluid temperature is used by the microprocessor to
determine the temperature drop across the cooler and is used in
determining the optimum time to add or subtract capacity
stages. The chilled fluid temperature set point can be automati-
cally reset by the return fluid temperature, space temperature or
outdoor-air temperature reset features. It can also be reset from
an external 4 to 20 mA signal (requires optional EMM), or
from a network signal.
The capacity control algorithm runs every 30 seconds. The
algorithm attempts to maintain the Control Point at the desired
set point. Each time it runs, the control reads the entering and
leaving fluid temperatures. The control determines the rate at
which conditions are changing and calculates 2 variables based
on these conditions. Next, a capacity ratio (SMZ, Outputs
under Sub-mode GEN.O) is calculated using the 2 variables to
determine whether or not to make any changes to the current
stages of capacity. This ratio value ranges from –100 to
+ 100%. If the next stage of capacity is a compressor, the con-
trol starts (stops) a compressor when the ratio reaches + 100%
(–100%). If the next stage of capacity is a loader, the control
energizes (deenergizes) a loader when the ratio reaches + 60%
(–60%). Loaders are allowed to cycle faster than compressors,
to minimize the number of starts and stops on each compressor.
A delay of 90 seconds occurs after each capacity step change.
MINUTES LEFT FOR START — This value is displayed in
the Status subfunction and represents the amount of time to
elapse before the unit is started. This value can be zero without
the machine running in many situations. This can include
being unoccupied, Remote Contact/Off/Enable switch in the
OFF position, CCN not allowing unit to start, Demand Limit in
effect, no call for cooling due to no load, and alarm or alert
conditions present. If the machine should be running and none
of the above are true, a minimum off time may be in effect.
The machine should start normally once the time limit has
expired.
8
The control system cycles com-