Honeywell International Inc. RTU-K12 用户手册
Power
Page 9
Power
The RTU is powered at low voltage (12V
DC
150mA) by a battery-operated
power supply module (RTU-Qxx). In order to determine the correct size for
power cables, refer to the table below. Max voltage cable drop = 1,0VDC for
assure that in battery power working, when battery min voltage is 10,5V the
min RTU power supply Î 9,5V (min RTU voltage).
power cables, refer to the table below. Max voltage cable drop = 1,0VDC for
assure that in battery power working, when battery min voltage is 10,5V the
min RTU power supply Î 9,5V (min RTU voltage).
Type of cable
Length (m) in relation to effective load
AWG
mm2
ohm/Km 150 [mA] 300 [mA] 600 [mA]
1,2 [A]
2,4 [A]
12
3,3
5,7
585
292
117
58
29
14
2
8,8
379
189
76
38
19
16
1,3
14
238
119
48
24
12
18
0,9
21
159
79
32
16
8
20
0,6
34
98
49
20
10
5
22
0,35
52
64
32
13
6
3
24
0,2
85
39
20
8
4
2
+12V Ground
When the cables go out-of-doors is mandatory to use shielded cables. The
cables’ shielding must be connected to the ground connector.
cables’ shielding must be connected to the ground connector.
For internal wiring without shielded cables is recommended an electrical
environment where the cables are well separated, even at short runs,
especially to the power cables or external cables which can be essentially
subjected to interference or lighting.
environment where the cables are well separated, even at short runs,
especially to the power cables or external cables which can be essentially
subjected to interference or lighting.