Rockwell Automation 1606-XLP50E Power Supply Reference Manual - Manual (Page 19)

All parameters are specified at 24V, 2.1A, 230Vac input, 25ªC ambient and after a 5 minutes run-in time unless noted otherwise.
Rockwell Automation Publication 1606-RM034A-EN-P — March 2014 19
Bulletin 1606 Switched Mode Power Supplies
Please note: This simple way to build a redundant system has two major disadvantages.
- The faulty power supply cannot be identified. The green LED will still be on since it is reverse-powered from
the other power supply.
- It does not cover failures such as an internal short circuit in the secondary side of the power supply. In such a
situation the defective unit becomes a load for the other power supplies and the output voltage can no
longer be maintained.
The above conditions can be avoided by using decoupling diodes which are included in the 1606-XLPRED
decoupling module.
Other recommendations for building redundant power systems:
a)
Use separate input fuses for each power supply.
b) Monitor the individual power s upply units. A DC-ok output is included in the 1606-XLP50E and 1606-XLP50EZ
In all other cases, use the the 1606-XLERED redundancy module which includes a monitoring circuit for
each input.
c) When possible, connect each power supply to different phases of the mains network.
26.6. Daisy Chaining of Outputs
Daisy chaining (jumping from one power supply output to the next) is allowed as long as the maximum current
through one terminal pin does not exceed 13A. If the current is higher, use a separate distribution terminal block.
Fig. 26-5 Daisy chaining of outputs Fig. 26-6 Using distribution terminals
Power
Supply
+ + - -
Input
Output
Load
+ -
max 13A!
Power
Supply
+ + - -
Input
Output
Load
+ -
Distribution
Terminals
Power
Supply
+ + - -
Input
Output
Power
Supply
+ + - -
Input
Output
26.7. Charging Batteries
The power supply can be used for float-charging of lead-acid or maintenance-free 24V VRLA batteries.
Instructions for charging batteries:
a)
Ensure that the ambient temperature of the power supply does not exceed 50°C.
b) Set the output voltage on a disconnected load, very precisely to the end-of-charge voltage according to the
expected battery temperature.
End-of-charge voltage
27.8V 27.5V 27.15V 26.8V
Battery temperature 10°C 20°C 30°C 40°C
c) Use a 4A or 6A circuit breaker (or blocking diode ) between the power supply and the battery.
d) Ensure that the output current of the power supply is below the allowed charging current of the battery.
e) Use only matched batteries when putting 12V types in series.
f) The return current to the power supply is typ. 10.7mA at 25Vdc when the power supply is switched off (except if
using a blocking diode).