User manual

CD5.241, CD5.241-S1
CD–Series
DC/DC Converter; 24V, 5A
Jan. 08 / Rev. 1.1 DS-CD5.241-EN / All parameters are specified at 24V, 5A and 24Vdc input at 25°C ambient unless otherwise noted.
www.pulspower.com Phone [phone] Germany
20/22
27.8. PARALLEL USE FOR 1+1 REDUNDANCY
DC/DC converters can be paralleled for 1+1 redundancy to gain a higher system availability. Redundant systems
require a certain amount of extra power to support the load in case one DC/DC converter unit fails. The simplest way
is to put two DC/DC converters in parallel. In case one converter fails, the other one is automatically able to support
the load current without any interruption.
Furthermore, redundant systems can be built by using a DC/DC converter powered from a battery and a power supply
with AC input.
- Use the decoupling module YR2.DIODE in combination with two CD5.241-S1 and use the DC-OK signals of the
DC/DC converter to monitor a faulty unit or input voltage.
- Use the redundancy module YRM2.DIODE in combination with two CD5.241 and use the DC-OK signals of the
redundancy module to monitor a faulty unit or input voltage.
Recommendations for building redundant power systems:
a) Use separate input fuses for each DC/DC converter.
b) Monitor the individual voltage sources of a redundant system. A DC-ok lamp and a DC-ok contact is included in
the redundancy module YRM2.DIODE and the DC/DC converter CD5.241-S1. This feature reports a faulty unit.
c) When possible, connect each DC/DC converter to different power sources.
27.9. CHARGING OF 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 6A or 10A 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. 26.4mA at 25Vdc when the power supply is switched off (except in
case a blocking diode is utilized).