2.On low-voltage compressors (600 v or less) connect a voltmeter across the power wires to the compressor start- er and measure the voltage. Compare this reading to the voltage rating on the compressor and starter nameplates.

3.Compare the ampere rating on the starter nameplate to rating on the compressor nameplate. The overload trip amps must be 108% to 120% of the rated load amps.

4.The starter for a centrifugal compressor motor must contain the components and terminals required for PIC II refrigeration control. Check the certified drawings.

5.Check the voltage to the following components and compare it to the nameplate values: oil pump contact, pumpout compressor starter, and power panel.

6.Ensure that fused disconnects or circuit breakers have been supplied for the oil pump, power panel, and pumpout unit.

7.Ensure all electrical equipment and controls are properly grounded in accordance with job drawings, certified drawings, and all applicable electrical codes.

8.Ensure the customer’s contractor has verified proper op- eration of the pumps, cooling tower fans, and associated auxiliary equipment. This includes ensuring motors are properly lubricated and have proper electrical supply and proper rotation.

9.For field-installed starters only, test the chiller compres- sor motor and its power lead insulation resistance with a 500-v insulation tester such as a megohmmeter. (Use a 5000-v tester for motors rated over 600 v.) Factory- mounted starters do not require a megohm test.

a.Open the starter main disconnect switch and follow lockout/tagout rules.

If the motor starter is a solid-state starter, the motor leads must be disconnected from the starter before an insulation test is performed. The voltage generated from the tester can damage the starter solid-state components.

b.With the tester connected to the motor leads, take 10-second and 60-second megohm readings as follows:

6-Lead Motor — Tie all 6 leads together and test between the lead group and ground. Next tie the leads in pairs: 1 and 4, 2 and 5, and 3 and 6. Test between each pair while grounding the third pair.

3-Lead Motor — Tie terminals 1, 2, and 3 together and test between the group and ground.

c.Divide the 60-second resistance reading by the 10-second reading. The ratio, or polarization index, must be one or higher. Both the 10- and 60-second readings must be at least 50 megohms.

If the readings on a field-installed starter are unsat- isfactory, repeat the test at the motor with the power leads disconnected. Satisfactory readings in this second test indicate the fault is in the power leads.

NOTE: Unit-mounted starters do not have to be megohm tested.

10.Tighten all wiring connections to the plugs on the ISM and CCM modules.

11.On chillers with free-standing starters, inspect the power panel to ensure that the contractor has fed the wires into the bottom of the panel. Wiring into the top of the panel can cause debris to fall into the contactors. Clean and in- spect the contactors if this has occurred.

Carrier Comfort Network Interface — The Carrier Comfort Network (CCN) communication bus wiring is sup- plied and installed by the electrical contractor. It consists of shielded, 3-conductor cable with drain wire.

The system elements are connected to the communication bus in a daisy chain arrangement. The positive pin of each sys- tem element communication connector must be wired to the positive pins of the system element on either side of it. The negative pins must be wired to the negative pins. The signal ground pins must be wired to the signal ground pins. See instal- lation manual.

NOTE: Conductors and drain wire must be 20 AWG (American Wire Gage) minimum stranded, tinned copper. Individual conductors must be insulated with PVC, PVC/ nylon, vinyl, Teflon, or polyethylene. An aluminum/polyester 100% foil shield and an outer jacket of PVC, PVC/nylon, chrome vinyl, or Teflon with a minimum operating tempera- ture range of –4 F to 140 F (–20 C to 60 C) is required. See table below for cables that meet the requirements.

MANUFACTURER

CABLE NO.

Alpha

2413 or 5463

American

A22503

Belden

8772

Columbia

02525

When connecting the CCN communication bus to a system element, a color code system for the entire network is recom- mended to simplify installation and checkout. The following color code is recommended:

 

CCN BUS

 

SIGNAL TYPE

CONDUCTOR

CCN TERMINAL

INSULATION

CONNECTION

 

 

COLOR

 

+

Red

RED (+)

Ground

White

WHITE (G)

Black

BLACK (–)

Check Starter

BE AWARE that certain automatic start arrangements can engage the starter. Open the disconnect ahead of the starter in addition to shutting off the chiller or pump.

Use the instruction and service manual supplied by the start- er manufacturer to verify the starter has been installed correct- ly, to set up and calibrate the starter, and for complete trouble- shooting information.

The main disconnect on the starter front panel may not deenergize all internal circuits. Open all internal and remote disconnects before servicing the starter.

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Carrier 19XR, XRV specifications Check Starter, Manufacturer Cable no, White G

19XR, XRV specifications

The Carrier 19XR and 19XRV chillers are sophisticated cooling solutions that represent the forefront of HVAC technology. Designed for large commercial and industrial applications, these chillers provide exceptional performance, energy efficiency, and reliability, making them ideal for a variety of environments ranging from hospitals to manufacturing facilities.

One of the most significant features of the Carrier 19XR and 19XRV chillers is their advanced scroll compressor technology. These units employ a tandem scroll design that enhances efficiency while minimizing operational noise. This makes them ideal for urban environments where noise restrictions may be in place. Moreover, the compressors are equipped with variable speed drive options in the 19XRV model, which allows for greater energy savings by adjusting cooling output based on real-time demand.

In addition to their advanced compressors, the 19XR and 19XRV units incorporate the Carrier GreenChoice refrigerant, which has a lower global warming potential compared to traditional refrigerants. This innovative choice not only meets regulatory requirements but also contributes to sustainability goals, making these chillers a responsible choice for environmentally conscious organizations.

The units are engineered with a robust heat exchanger design, which enhances heat transfer efficiency and overall system performance. This ensures optimal operation even in extreme conditions. They feature a microprocessor-based control system that allows for precise monitoring and control of the chiller’s performance, enabling operators to make real-time adjustments to maximize energy efficiency.

The Carrier 19XR and 19XRV chillers also prioritize serviceability. The design incorporates easy access to key components, simplifying maintenance procedures and reducing downtime. This focus on maintainability extends the lifespan of the equipment, leading to lower lifecycle costs.

In terms of connectivity, these chillers are equipped with advanced Building Management System (BMS) integration capabilities. This allows for seamless monitoring and control of the chillers using a centralized platform, facilitating energy management and operational optimization.

Overall, the Carrier 19XR and 19XRV chillers stand out in the market for their blend of cutting-edge technology, energy efficiency, and user-friendly features. They are engineered to meet the demanding needs of modern commercial and industrial applications, making them a preferred choice for facility managers seeking reliable cooling solutions.