Rockwell Automation T80002 Application Note Replacement of Power Supplies - Manual

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AN-T80002
Issue 1 Feb 07 AN-T80002 1
Application Note
Replacement of Power Supplies
Older ICS systems have used power supplies which are now nearing the end of their life or are no
longer available. These systems cannot be repaired using direct supply replacement and therefore
need alternative supplies.
ICS Triplex Technology recommends the use of T824x series power supplies, which in most cases
should fit into spare panel space. Each supply chassis uses 1U of rack space and can fit three 750W
supplies, each providing 24V or 28V from one AC feed. A dual supply providing 1500W with a spare
supply on each feed can therefore be mounted in 2U of rack space.
These replacement supplies should be fitted completely before transferring duty from the old to the
new supplies. Do not fit replacement supplies that partly share duty with existing supplies;
nonlinearities in existing supplies may prove difficult to track in the power sharing circuits of
replacement supplies, which could cause them to trip on overload.
Note that existing supplies may have their own circuit breakers/isolation switches, bridging diodes and
power failure relays. These must be replicated in the new design. T824x series supplies will need
circuit breakers. Bridging diodes are only necessary where linking dual redundant supplies into one
feed, to protect against an output short in one supply. Each T8240 chassis may be fitted with a T8243
power port which provides failure relays for AC feed and DC output.
Issue Record
Issue
Number Date Revised by Technical
Check Authorised by Modification
1 Feb 07 Nick Owens Ray Brown Pete Stock Initial Issue