Current Transformer And Potential; Transformer Wire Sizing - Trane CenTraVac CDHH Installation, Operation And Maintenance Manual

Current Transformer and
Potential Transformer Wire
Sizing
For customer-supplied starter-to-chiller unit control panel
starter module 1K23; these wires must be separated from
120 Vac or higher wiring.
Table 19. Maximum recommended wire length for
secondary current transformer (CT) leads in
dual CT system
Wire AWG (a)
8
10
12
14
16
17
18
20
Notes:
1. For AWG/MCM equivalents in mm
Requirements," p. 53.
2. Wire length is for copper conductors only.
3. Wire length is total one-way distance that the CT can be from the starter
module.
(a) Wires, lugs, and fuses/breakers are sized based on National Electric Code
(NEC) [NFPA 70] and UL 1995.
CDHH-SVX003C-EN
Maximum Wire Length
Secondary CT Leads
Feet Meters
1362.8 415.5
856.9 261.2
538.9 164.3
338.9 103.3
213.1 65.0
169.1 51.5
134.1 40.9
84.3 25.7
2
, refer to the table in "Electrical
Customer-supplied Remote Starter Wiring
Table 20. Maximum recommended total wire length
for potential transformers (PTs) in a single
PT system
Wire AWG (a)
8
10
12
14
16
17
18
20
21
22
Notes:
1. For AWG/MCM equivalents in mm
Requirements," p. 53.
2. Wire length is for copper conductors only.
3. Wire length is maximum round trip wire length. The maximum distance
the PT can be located from the starter module is half of the listed value.
(a) Wires, lugs, and fuses/breakers are sized based on National Electric Code
(NEC) [NFPA 70] and UL 1995.
Table 21. Maximum recommended total wire length
(to and from) for PT leads in a dual PT
system
Max Wire Length Primary
Wire AWG (a)
Feet
8 3061
10 1924
12 1211
14 761
16 478
17 379
18 301
20 189
21 150
22 119
Notes:
1. For AWG/MCM equivalents in mm
Requirements," p. 53.
2. Wire length is for copper conductors only.
3. Wire length is maximum round trip wire length. The maximum distance
the PT can be located from the starter module is half of the listed value.
(a) Wires, lugs, and fuses/breakers are sized based on National Electric Code
(NEC) [NFPA 70] and UL 1995.
Maximum Lead Length
Feet Meters
5339 1627
3357 1023
2112 643
1328 404
835 254
662 201
525 160
330 100
262 79
207 63
2
, refer to the table in "Electrical
Max Wire Length
Secondary
Meters Feet Meters
933 711 217
586 447 136
369 281 85
232 177 53
145 111 33
115 88 26
91 70 21
57 44 13
45 34 10
36 27 8
2
, refer to the table in "Electrical
57