Wiring Of Outdoor Unit; Connecting Power Cables For Outdoor Unit; Connecting Control Signal Cables Of Outdoor Unit - Liebert DM User Manual

26 Chapter 3 Electrical Installation

3.3 Wiring Of Outdoor Unit

3.3.1 Connecting Power Cables For Outdoor Unit

1. Identifying the cable specifications
Select the power supply cables and the start/stop signal cables of the condenser according to the fan rated operation
current (see Table 3-2) and the site conditions, such as the distance between indoor unit and condenser.

Note
1. The 20AWG (0.52mm
2. The protected tube or shielded line is required for the outdoor part of the connection cable between the indoor unit and the
condenser. The ground cable should be connected to the ground nearby, and the length cannot exceed 3m.
3. The cables cannot contact with hot objects, such as the copper tube and water pipe without insulation, to avoid damaging the
insulation layers.
4. The cables should be connected in accordance with the local regulations.
2. Connecting cables
See Figure3-5 and Appendix 3 Circuit Diagram of DMC16M2 for the connections of external power cables.
Waterproof connector of external
Water joint of external
power accessing lines
power cables
Figure 3-5 Connection figure of single fan external power cables (taking LDF42 for example)

Note
1. The external power lines and compressor signal lines enter the electrical controlling box through the water joint of external
power cables whose inside diameter is Φ10mm.
2. After connecting the external power lines, the waterproof sealant treatment is required to ensure the good waterproof
performance of electrical controlling box.
3. The phase order of three-phase AC input (L1, L2, L3) must be correct. Otherwise, the fan speed controller will generate the
phase loss alarm, and there will be no AC output.

3.3.2 Connecting Control Signal Cables Of Outdoor Unit

The wiring terminals are located on the fan speed controller board (see Figure3-5). Their distribution is shown in
Figure3-6 and the definitions are listed in Table3-3. Refer to Appendix 3 Circuit Diagram of DMC16M2 for detailed
connections.
Table 3-2 Operation current of fan under 380V voltage
Condenser Model
DMC16M2
2
) start / stop signal cable of the condenser is recommended.
外部电源进
线防水接头
Accessing terminal of external
power supply (single fan)
DM Series 16kW Air Conditioner User Manual
外部电源接入端（单风机）
Rated current (A)
1.65
风机转速控制器单板
Fan speed controller board