Carrier XRV, 19XR specifications Starting Equipment, Unit-Mounted Solid-State Starter Optional

REAR MOTOR	FWD MOTOR		OIL SUPPLY TO
BEARING	BEARING		FORWARD HIGH
		LABYRINTH	SPEED BEARING
		GAS LINE

MOTOR

COOLING LINE

					ISOLATION
					VALVE
TXV BULB	PRESSURE	ISOLATION		OIL	FILTER
				PUMP
	TRANSDUCER	VALVE		OIL	SIGHT
		OIL
			OIL PUMP	HEATER	GLASS
		COOLER			EDUCTOR FILTER
			MOTOR
				SIGHT GLASS	ISOLATION
					VALVE

OIL SKIMMER LINE

Fig. 4 — Lubrication System

STARTING EQUIPMENT

The 19XR requires a motor starter to operate the centrifugal hermetic compressor motor, the oil pump, and various auxilia- ry equipment. The starter is the main field wiring interface for the contractor.

See Carrier Specification Z-415 for specific starter require- ments, Z-416 for free-standing VFD requirements and Z-417 for unit-mounted VFD requirements. All starters must meet these specifications in order to properly start and satisfy me- chanical safety requirements. Starters may be supplied as sepa- rate, free-standing units or may be mounted directly on the chiller (unit mounted) for low voltage units only.

Three separate circuit breakers are inside the starter. Circuit breaker CB1 is the compressor motor circuit breaker. The dis- connect switch on the starter front cover is connected to this breaker. Circuit breaker CB1 supplies power to the compressor motor.

The main circuit breaker (CB1) on the front of the starter disconnects the main motor current only. Power is still energized for the other circuits. Two more circuit breakers inside the starter must be turned off to disconnect power to the oil pump, PIC II controls, and oil heater.

Circuit breaker CB2 supplies power to the control panel, oil heater, and portions of the starter controls.

Circuit breaker CB3 supplies power to the oil pump. Both CB2 and CB3 are wired in parallel with CB1 so that power is supplied to them if the CB1 disconnect is open.

All starters must include a Carrier control module called the Integrated Starter Module (ISM), excluding the Benshaw

solid-state starters. This module controls and monitors all as- pects of the starter. See the Controls section on page 10 for ad- ditional ISM information. All starter replacement parts are sup- plied by the starter manufacturer excluding the ISM (contact Carrier’s Replacement Component Division [RCD]).

Unit-Mounted Solid-State Starter (Optional) —

The 19XR chiller may be equipped with a solid-state, reduced- voltage starter (Fig. 5 and 6). This starter’s primary function is to provide on-off control of the compressor motor. This type of starter reduces the peak starting torque, reduces the motor in- rush current, and decreases mechanical shock. This capability is summed up by the phrase “soft starting.” The solid-state starter is available as a 19XR option (factory supplied and in- stalled). The solid-state starters manufacturer name is located inside the starter access door.

A solid-state, reduced-voltage starter operates by reducing the starting voltage. The starting torque of a motor at full volt- age is typically 125% to 175% of the running torque. When the voltage and the current are reduced at start-up, the starting torque is reduced as well. The object is to reduce the starting voltage to just the voltage necessary to develop the torque re- quired to get the motor moving. The voltage is reduced by sili- con controlled rectifiers (SCRs). The voltage and current are then ramped up in a desired period of time. Once full voltage is reached, a bypass contactor is energized to bypass the SCRs.

When voltage is supplied to the solid-state circuitry (CB1 is closed), the heat sinks in the starter as well as the wires leading to the motor and the motor terminal are at line volt- age. Do not touch the heat sinks, power wiring, or motor terminals while voltage is present or serious injury will result.

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