Daikin DAX Series, Руководство по установке

Страница: 6 / 16

6
Building Electrical Service Inspection
This unit is designed for 3-phase operation. DO NOT
OPERATE ON A SINGLE PHASE POWER SUPPLY. SEE
THE PRECEDING WARNING. Measure the power supply
to the unit. The supply voltage must be in agreement with
the unit nameplate power requirements and within the
range shown below:
Nominal
Minimum
Supply Voltage
Maximum
Supply Voltage
208 - 230 197 253
460 414 506
Voltage Balance: The supply voltage shall be unbalance
(phase to phase) within 2%. To calculate the percentage of
voltage unbalance use the following formula:
Percentage Max Voltage Deviation From Average
Voltage Unbalance = 100 x Average Voltage
Example: L1 – L2 = 220 V
L2 – L3 = 216 V
L1 – L3 = 213 V
Avg. Voltage: = (220+216+213) / 3
= 649 / 3
= 216
Max. Deviation from Avg. = 220 – 216 = 4
% Voltage Unbalance = 100 x (4 / 216)
= 400 / 216
= 1.8%
Determine Wire Size: The selection of the appropriate
supply wire size is important to the operation of the
equipment. When selecting the wire size the following are
important elements of the decision:
• The wire size is adequately sized to carry the
Minimum Circuit Ampacity (MCA). Refer to the NEC
(USA) or CSA (Canada) for wire sizing. The unit MCA
for the airhandler and the optional electric heat kit
can be found on the equipment S&R plate and the
following table.
AIRHANDLER VOLTAGE HEAT KIT MCA
DAX0904 and
DAX1204
208 - 230
None 15.5 / 15.5
AHKD15-3A 56.3 / 62.4
AHKD20-3A 69.4 / 77.4
AHKD30-3A 95.4 / 108
460
None 5.2
AHKD15-4A 28.3
AHKD20-4A 35.8
AHKD30-4A 50.9
Wire Sizing
Wire size is important to the operation of your equipment.
Use the following check list when selecting the appropriate
wire size for your unit.
• Wire size must carry the Minimum Circuit
Ampacity (MCA).
• Refer to the NEC (USA) or CSA (Canada) for wire
sizing. The unit MCA for the air handler and the
optional electric heat kit can be found on the unit
Series and Rating Plate.
• Wire size allows for no more than a 2% voltage
drop from the building breaker/fuse panel to the
unit.
Refer to the latest edition of the National Electric
Code or in Canada the Canadian Electric Code when
determining the correct wire size. The following table
shows the current carrying capabilities for copper
conductors rated at 75 ° C with a 2% voltage drop.
Use this table determine the voltage drop per foot of
various conductors.
MAXIMUM ALLOWABLE LENGTH IN FEET TO LIMIT
VOLTAGE DROP TO 2%
Wire Size
(AWG) 10 15 20 25 30 35 40 45
14
77 51 38 NR NR NR NR NR
12 122 81 61 49 NR NR NR NR
10
193 129 97 77 64 55 NR NR
8
307 205 154 123 103 88 77
68
6 489 326 244 195 163 140 122 109
Minimum Circuit Ampacity (MCA)
Maximum Overcurrent Protection (MOP)
Every installation must include an NEC (USA) or CEC
(Canada) approved overcurrent protection device. Also,
check with local or state codes for any special regional
requirements.
Protection can be in the form of fusing or HACR style
circuit breakers. The Series and Rating Plate can be used
as a guide for selecting the MAXIMUM overcurrent device
or reference the following table.
NOTE: Fuses or circuit breakers are to be sized
larger than the equipment MCA but not to exceed
the MOP.
AIRHANDLER VOLTAGE HEAT KIT MOP
DAX0904 and
DAX1204
208 - 230
None 20 / 20
AHKD15-3A 60 / 70
AHKD20-3A 70 / 80
AHKD30-3A 100 / 110
460
None 15
AHKD15-4A 30
AHKD20-4A 40
AHKD30-4A 60