Carrier 19XL Denitions, Controls, Major PIC Components Panel Locations, PIC Component Panel, Psio

·overtemperature

·ground fault

·current unbalance

·run state

These LEDs are further explained in the Check Starter and Troubleshooting Guide section, page 66.

Unit-Mounted Wye-Delta Starter (Optional) Ð The 19XL chiller may be equipped with a wye-delta starter mounted on the unit (Fig. 7). This starter is intended for use with low- voltage motors (under 600 v). It reduces the starting current inrush by connecting each phase of the motor windings into a wye con®guration. This occurs during the starting period when the motor is accelerating up to speed. After a time de- lay, once the motor is up to speed, the starter automatically connects the phase windings into a delta con®guration.

1 2 3 4 5 6 7

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16	8
15

14 13 12 11 10 9

LEGEND

1Ð Pilot Relays

2Ð SMM Power Circuit Breaker and Voltage Calibration Potentiometer

3Ð Transistor Resistor Fault Protector (TRFP)

4Ð Transformer (T2)

5Ð Control Power Circuit Breaker

6Ð Oil Pump Circuit Breaker

7Ð Main Circuit Breaker Disconnect

8Ð Voltmeter (Optional)

9Ð Ammeter (Optional)

10Ð Current Transformers (T1, T2, T3)

11Ð Phase Monitor Relay (Optional)

12Ð Overload Unit

13Ð Starter Management Module

14Ð Starter Access Door

15Ð Control Transformer Secondary Circuit Breaker

16Ð Signal Resistor

17Ð Field Wiring Terminal Strip (TB6)

Fig. 7 Ð Wye-Delta Starter, Internal View

The memory of the PSIO and LID modules are volatile. If the battery in a module is removed or damaged, all programming will be lost.

General Ð The 19XL hermetic centrifugal liquid chiller contains a microprocessor-based control center that moni- tors and controls all operations of the chiller. The micro- processor control system matches the cooling capacity of the chiller to the cooling load while providing state-of-the-art chiller protection. The system controls cooling load within the set point plus the deadband by sensing the leaving chilled water or brine temperature, and regulating the inlet guide vane via a mechanically linked actuator motor. The guide vane is a variable ¯ow prewhirl assembly that controls the refrigeration effect in the cooler by regulating the amount of refrigerant vapor ¯ow into the compressor. An increase in guide vane opening increases capacity. A decrease in guide vane opening decreases capacity. Chiller protection is pro- vided by the processor which monitors the digital and ana- log inputs and executes capacity overrides or safety shutdowns, if required.

PIC System Components Ð The Product Integrated Control (PIC) is the control system on the chiller. See Table 1. The PIC controls the operation of the chiller by moni- toring all operating conditions. The PIC can diagnose a prob- lem and let the operator know what the problem is and what to check. It promptly positions the guide vanes to maintain leaving chilled water temperature. It can interface with aux- iliary 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 Net- work (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 Ð all extra low-voltage wiring (24 v or less)

·power panel Ð 230 or 115 v control voltage (per job requirement)

Ðup to 600 v for oil pump power

·starter cabinet Ð chiller power wiring (per job requirement)

Table 1 Ð Major PIC Components and

Panel Locations*

De®nitions

CONTROLS

PIC COMPONENT	PANEL
	LOCATION
Processor Sensor Input/Output Module	Control Center
(PSIO)

ANALOG SIGNAL Ð An analog signal varies in propor- tion to the monitored source. It quanti®es values between operating limits. (Example: A temperature sensor is an ana- log device because its resistance changes in proportion to the temperature, generating many values.)

DIGITAL SIGNAL Ð A digital (discrete) signal is a 2-position representation of the value of a monitored source. (Ex- ample: A switch is a digital device because it only indicates whether a value is above or below a set point or boundary by generating an on/off, high/low, or open/closed signal.)

VOLATILE MEMORY Ð Volatile memory is memory in- capable of being sustained if power is lost and subsequently restored.

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 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. 8
Pressure Transducers	See Fig. 8
*See Fig. 5, 6, and Fig. 8-12.

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