Revision A4 : August, 2009
Page. 8
THR4-SSERIES POWER SYSTEM
For this example we will assume that future growth is necessary so we will size the AC feed for
four power modules. Using Table 4, each AC feed, to the pair of TH120048, power modules will
require will require a 20 amp breaker with 12 AWG wire, at high line, per feed.
NOTE: Under-sizing your AC breaker and wiring could cause nuisance breaker trips and system
outages. ALWAYS FOLLOW NEC RULES AND YOUR LOCAL COMPANY PRACTICES WHEN
SELECTING DC WIRING AND PROTECTION.
The Table 4 below uses a minimum nominal input voltage to determine AC current requirements.
90 V corresponds to a nominal low line voltage of 100VAC and 180 V corresponds to a nominal
highline voltage of 200VAC.
Individual
Feed
Dual
Feed
Recommended AC Circuit Breaker & Wire Sizes
Number of
Model #
Minimum
Maximum
Circuit Breaker
90°C Minimum Wire
Type of
Power Modules
of Power
Input
rated AC
Minimum Value Gauge to use at 30°C
Feed
on AC Feed
Module
Voltage
Current (Amps)
to use (Amps)
ambient (AWG)
TH120048
90
17.6
20
12
TH120048
180
8.8
15
14
TH200048
180
13.8
15
14
TH250048
180
16.9
20
12
TH200036
180
9
15
14
TH120024
90
17.4
20
12
TH120024
180
8.7
15
14
TH120012*
90
15
15
12
TH120012
180
8.9
15
14
TH120048
90
35.2
N/A
N/A
TH120048
180
17.6
20
12
TH200048
180
27.6
30
10
TH250048
180
33.8
N/A
N/A
TH200036
180
9
20
12
TH120024
180
17.4
20
12
TH120012*
90
30
30
10
TH120012
180
17.8
20
12
*1200W
Table 4
1
2
