PIC System Components —
The Product Integrated
Control (PIC) is the control system on the machine. See
Table 1. The PIC controls the operation of the machine by
monitoring all operating conditions. The PIC can diagnose
a problem and let the operator know what the problem is and
what to check. It promptly positions the guide vanes to main-
tain leaving chilled water temperature. It can interface with
auxiliary equipment such as pumps and cooling tower fans
to turn them on only when required. It continually checks all
safeties to prevent any unsafe operating condition. It also
regulates the oil heater while the compressor is off, and the
hot gas bypass valve, if installed.
The PIC can be interfaced with the Carrier Comfort
Network (CCN) if desired. It can communicate with other
PIC-equipped chillers and other CCN devices.
The PIC consists of 3 modules housed inside the 3 major
components. The component names and the control voltage
contained in each component are listed below (also see
Table 1):
• control center
— all extra low-voltage wiring (24 v or less)
• power panel
— 115 v control voltage
— up to 600 v for oil pump power
• starter cabinet
— machine power wiring (per job requirement)
Table 1 — Major PIC Components and
Panel Locations*
PIC COMPONENT
PANEL
LOCATION
Processor Sensor Input/Output Module (PSIO) Control Center
Starter Management Module (SMM)
Starter Cabinet
Local Interface Device (LID)
Control Center
6-Pack Relay Board
Control Center
8-Input Modules (Optional)
Control Center
Oil Differential Pressure/Power Supply
Module
Control Center
Oil Heater Contactor (1C)
Power Panel
Oil Pump Contactor (2C)
Power Panel
Hot Gas Bypass Relay (3C) (Optional)
Power Panel
Control Transformers (T1-T4)
Power Panel
Control and Oil Heater Voltage Selector (S1)
Power Panel
Temperature Sensors
See Fig. 10
Pressure Transducers
See Fig. 11
*See Fig. 7-13.
PROCESSOR MODULE (PSIO) — This module contains
all of the operating software needed to control the machine.
The open-drive machines use a different software package
within the PSIO than the hermetic machines. There are also
control hardware differences between the two types of ma-
chines. The 19EX uses 3 pressure transducers and 8 ther-
mistors to sense pressures and temperatures. The 17EX uses
4 pressure transducers and 7 thermistors to sense pressures
and temperatures.
These inputs are connected to the PSIO module. The PSIO
also provides outputs to the: guide vane actuator; oil pump;
oil heater; hot gas bypass (optional); motor cooling sole-
noid; and alarm contact. The PSIO communicates with the
LID, the SMM, and the optional 8-input modules for user
interface and starter management.
STARTER MANAGEMENT MODULE (SMM) — This mod-
ule is located within the starter cabinet. This module ini-
tiates PSIO commands for starter functions such as start/
stop of the compressor, start/stop of the condenser and chilled
water pumps, start/stop of the tower fan, spare alarm con-
tacts, and the shunt trip. The SMM monitors starter inputs
such as flow switches, line voltage, remote start contact, spare
safety, condenser high pressure, oil pump interlock, motor
current signal, starter 1M and run contacts, and kW trans-
ducer input (optional). The SMM contains logic capable of
safely shutting down the machine if communication with
the PSIO is lost.
LOCAL INTERFACE DEVICE (LID) — The LID is mounted
to the control center and allows the operator to interface with
the PSIO or other CCN devices. It is the input center for all
local machine set points, schedules, set-up functions, and op-
tions. The LID has a STOP button, an alarm light, 4 buttons
for logic inputs, and a display. The function of the 4 buttons
or ‘‘softkeys’’ are menu driven and are shown on the display
directly above the key.
6-PACK RELAY BOARD — This device is a cluster of
6 pilot relays located in the control center. It is energized by
the PSIO for the oil pump, oil heater, alarm, optional hot gas
bypass relay, and motor cooling solenoid (19EX machines)
on auxiliary oil pump (17EX machines).
8-INPUT MODULES — One optional module is factory in-
stalled in the control center panel when ordered. There can
be up to 2 of these modules per chiller with 8 spare inputs
each. They are used whenever chilled water reset, demand
reset, or reading a spare sensor is required. The sensors or 4
to 20 mA signals are field-installed.
The spare temperature sensors must have the same
temperature/resistance curve as the other temperature sen-
sors on this unit. These sensors are rated 5,000 ohm at 75 F
(25 C).
OIL HEATER CONTACTOR (1C) — This contactor is lo-
cated in the power panel and operates the heater at 115 v. It
is controlled by the PIC to maintain oil temperature during
machine shutdown.
OIL PUMP CONTACTOR (2C) — This contactor is located
in the power panel. It operates all 200 to 575-v oil
pumps. The PIC energizes the contactor to turn on the oil
pump as necessary.
HOT
GAS
BYPASS
CONTACTOR
RELAY
(3C)
(Optional) — This relay, located in the power panel, con-
trols the opening of the hot gas bypass valve. The PIC en-
ergizes the relay during low load, high lift conditions.
OIL AUXILIARY RELAY (4C) — This relay, supplied only
with open-drive machines, opens the oil cooler solenoid valve
and interlocks the oil pump with the compressor.
CONTROL TRANSFORMERS (T1-T4) — These trans-
formers are located in the power panel and convert incom-
ing control voltage to either 21 vac power for the PSIO module
and options modules, or 24 vac power for 3 power panel
contactor relays and a control solenoid valve.
CONTROLAND OIL HEATER VOLTAGE SELECTOR (S1)
— It is necessary to use 115 v incoming control power in the
power panel. The switch must be set to the 115-v position.
OIL
DIFFERENTIAL
PRESSURE/POWER
SUPPLY
MODULE — This module, which is located in the control
center, provides 5 vdc power for the transducers and LID
backlight.
On open-drive machines, this module outputs the differ-
ence between two pressure transducer input signals. The mod-
ule subtracts oil supply pressure from transmission sump
pressure and outputs the difference as an oil differential pres-
sure signal to the PSIO. The PSIO converts this signal to
differential oil pressure. To calibrate this reading, refer to
the Troubleshooting, Checking Pressure Transducers.
14
Summary of Contents for 17
Page 13: ...Fig 6 Open Drive 17 Series Lubrication Cycle 13 ...
Page 15: ...Fig 7 17EX Controls and Sensor Locations 15 ...
Page 16: ...Fig 7 17EX Controls and Sensor Locations cont 16 ...
Page 17: ...Fig 7 17EX Controls and Sensor Locations cont 17 ...
Page 19: ...Fig 8 19EX Controls and Sensor Locations cont 19 ...
Page 23: ...Fig 16 17 19EX LID Menu Structure 23 ...
Page 24: ...Fig 17 17 19EX Service Menu Structure 24 ...
