NOTES:
IGENERAL
1.0Starters shall be designed and manufactured in accordance with Carrier Engineering requirement
1.1All
1.2The routing of
1.3Equipment installation and all starting and control devices must comply with details in equipment submittal drawings and literature.
1.4Contacts and switches are shown in the position they would assume with the circuit deenergized and the chiller shut down.
1.5WARNING: Do not use aluminum conductors.
1.6Installer is responsible for any damage caused by improper wiring be- tween starter and machine.
IIPOWER WIRING TO STARTER
2.0Power conductor rating must meet minimum unit nameplate voltage and compressor motor RLA (rated load amps). When (3) conductors are used:
Minimum ampacity per conductor =1.25 x compressor RLA
When (6) conductors are used:
Minimum ampacity per conductor =0.721 x compressor RLA.
2.1Lug adapters may be required if installation conditions dictate that con- ductors be sized beyond the minimum ampacity required. Contact starter supplier for lug information.
2.2Compressor motor and controls must be grounded by using equip- ment grounding lugs provided inside starter enclosure.
IIICONTROL WIRING
3.0Field supplied control conductors to be at least 18 AWG (American Wire Gage), or larger.
3.1Chilled water and condenser water ¯ow switch contacts, optional re- mote start device contacts, and optional spare safety device contacts must have 24 vdc rating. Maximum current is 60 ma, nominal current is 10 ma. Switches with gold plated bifurcated contacts are recommended.
3.2Remove jumper wire between 12A and 12B before connecting auxiliary safeties between these terminals.
3.3Maximum load on pilot relays is 10 amps. Pilot relays can control cooler and condenser pump and tower fan motor contactor coil loads rated up to 10 amps at 115 vac or up to 3 amps at 600 vac. Control wiring re- quired for Carrier to start pumps and tower fan motors must be pro- vided to assure machine protection. If primary pump and tower motor control is by other means, also provide a parallel means for control by Carrier. Do not use starter control transformer as the power source for pilot relay loads.
3.4Do not route control wiring carrying 30 v or less within a conduit which has wires carrying 50 v or higher or along side wires carrying 50 v or higher.
3.5Voltage selector switch in machine power panel is factory set for 115 v control and oil heater power source. The 230 v position is not used. If switch is set to 230 v position, oil heater will not operate.
3.6Control wiring cables between starter and power panel must be shielded with minimum rating of 600 v, 80 C. Ground shield at starter. Wires A, B, and C are communication wires and must be run in a separate cable.
3.7If optional oil pump circuit breaker is not supplied within the starter en- closure as shown, it must be located within sight of the machine with wiring routed to suit.
3.8Voltage to terminals LL1 and LL2 comes from a control transformer in a starter built to Carrier speci®cations. Do not connect an outside source of control power to the compressor motor starter (terminals LL1 and LL2). An outside power source will produce dangerous voltage at the line side of the starter, because supplying voltage at the transformer secondary terminals produces input level voltage at the transformer pri- mary terminals.
IV POWER WIRING BETWEEN STARTER AND COMPRESSOR MOTOR
4.0Medium voltage (over 600 volts) hermetic compressor motors have 3 terminals. Use no. 4 AWG strand wires for all medium and high volt- age hermetic motors. Distance between terminal is 79¤16 inches. Use suitable splice connectors and insulation for
4.1When more than one conduit is used to run conductors from starter to compressor motor terminal box, one conductor from each phase must be in each conduit, to prevent excessive heating, (e.g., conductors to motor terminals 1, 2, and 3 in one conduit, and those to 1, 2, and 3 in another).
4.2Compressor motor power connections can be made through top, top rear, or sides of compressor motor terminal box by using holes cut by contractor to suit conduit. Flexible conduit should be used for the last few feet to the terminal box for unit vibration isolation. Use of stress cones may require an oversize (special) motor terminal box (not sup- plied by Carrier).
4.3Compressor motor frame to be grounded in accordance with the Na- tional Electrical Code
4.4Do not allow motor terminals to support weight of wire cables, use cable supports and strain reliefs as required.
Fig. 18 Ð Field Wiring (High Voltage Motors) with Optional Free-Standing Starter (cont)
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