SECTION
DRY-TYPE DISTRIBUTION TRANSFORMERS
ACME ELECTRIC
•
MILWAUKEE, WI
•
800.334.5214
•
acmetransformer.com
31
PRIMARY (INPUT): 480 VOLTS
SECONDARY (OUTPUT): 480Y/277 VOLTS
3Ø, 3 WIRE
①
50/60 Hz
3Ø, 4 WIRE
①
Applicable for the above connection only.
②
Connection diagram (using 3 pieces of 1 phase, 60 hertz transformers connected zig-zag auto) for developing a neutral (4th wire) from a 3 phase,
3 wire supply.
③
For proper over-current protection, refer to the N.E.C. Article 450-5.
④
For transformer dimensions, refer to appropriate table in section 1, page 17.
Each Acme transformer is shipped with detailed wiring diagrams. Refer to nameplate located inside the front
cover for specific voltage tap combinations.
NEUTRAL
B
POINT
A,B OR C
TO
NEUTRAL
YIELDS
277 V
SINGLE
PHASE
4 WIRE
C
A
B
C
A
INPUT
480 V
3Ø
3 WIRE
B
C
A
X
X
X
X
X
H
H
H
H
X
X
X
X
H
H
H
H
X
X
X
H
H
H
H
COMMON TRIP DEVICE
NEUTRAL
TRANS. #3
TRANS. #2
TRANS. #1
See Footnote
②
O
= Fuse Location NEC 450-4, 1990.
③
Use 3 Pieces
Nameplate
No. of
Max. Continuous
of
Available
kVA
Tfmr.
Three Phase
Amp. Load Per
Type No.
④
In
For Each Tfmr.
Required
kVA
Phase
(277 Volts)
T253010S
No Taps Only
1.0
3
10.80
12.50
T253011S
No Taps Only
1.5
3
15.60
18.75
T253012S
No Taps Only
2.0
3
20.70
25.00
T2530134S
Taps & No Taps
3.0
3
31.20
37.50
T2530144S
Taps & No Taps
5.0
3
51.90
62.50
T2535153S
With Taps Only
7.5
3
78.00
93.50
T2535163S
With Taps Only
10.0
3
103.80
125.00
T2535173S
With Taps Only
15.0
3
156.00
187.50
T2535183S
With Taps Only
25.0
3
259.50
312.00
TP530193S
With Taps Only
37.5
3
390.00
468.00
TP530203S
With Taps Only
50.0
3
519.00
625.00
TP530213S
With Taps Only
75.0
3
780.00
935.00
TP530223S
With Taps Only
100.0
3
1038.00
1250.00
TP530233S
With Taps Only
167.0
3
1734.00
2085.00
Auto Zig-Zag Grounding Transformers
For developing a neutral from a three phase, 3-wire supply
