Rockwell Automation 1606-XLE80E, Руководство пользователя

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Rockwell Automation
1606-XLE80E-2 24V, 3.3A; Single Phase Input
10000108328
(Version 00)
www.ra.rockwell.com
Page 18
26.4. O
UTPUT
C
IRCUIT
B
REAKERS
Standard miniature circuit breakers (MCBs) can be used for branch protection. Ensure that the MCB is rated for DC voltage, too. The following tests
show which circuit breakers the power supply typically trips.
Circuit breakers have large tolerances in their tripping behavior. Therefore, these typical tests can only be used as a recommendation or for comparing
two different power supplies. Furthermore, the loop impedance has a major influence on whether a breaker trips or not. Two tests were performed,
representing typical situations:
Test 1: Short circuit with S1 on the power supply end of the cable (loop impedance approx. 20mOhm)
Fig. 26-3 Branch protectors, test circuit 1
Circuit
Breaker
Power
Supply
AC
DC
+
-
I
Load
+
-
S1
Parameters:
Input voltage:
230Vac, load current: 0A
The following circuit breaker tripped during the test:
A- or Z- Characteristic::
equal or smaller 6A
B- Characteristic: no tripping
≥
6A
no breaker available < 6A
C- Characteristic: equal or smaller 1A
Test 2: Short circuit with S1 on the load end (additional impedance included; represents longer load wire length).
Fig. 26-4 Branch protectors, test circuit 2
R
Circuit
Breaker
Power
Supply
AC
DC
+
-
I
S1 Load
+
-
Parameters:
Input voltage:
230Vac, load current: 0A
The following circuit breaker tripped during the test:
A- or Z- Characteristic::
≤ 4A and R= 220mOhm
B- Characteristic: no tripping
≥
6A
no breaker available < 6A
C- Characteristic: ≤ 1A and R= 390mOhm
What does this resistance mean in wire length?
0.5mm
2
0.7mm
2
1.0mm
2
1.5mm
2
2.5mm
2
4.0mm
2
220mOhm 6.1m 8.6m 12.3m 18.4m 30.6m 49m
390mOhm 10.9m 15.2m 21.7m 32.6m 54.3m 86.9m
Example:
Which wire gauge must be used to trip a C-Characteristic circuit breaker with a rating of 1A? The load wire length is 25m.
Answer: A 1A C-Characteristic circuit breaker requires a loop impedance of less than 390mOhm (test results). The wire length table shows that up to
32.6m wire with a cross section of 1.5mm
2
are below 390mOhm. A wire not smaller than 1.5mm
2
shall be used.
26.5. I
NDUCTIVE AND
C
APACITIVE
L
OADS
The unit is designed to supply any type of load, including unlimited capacitive and inductive loads.