Honeywell HPM, Service

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2 Equipment Description
2.23 I/O Link Interface Cabling
R688 HPM High-Performance Process Manager Service 129
December 2020 Honeywell
I/O Link Interface Cables in adjacent cabinets
The I/O Link Interface cable daisy chain can be extended to include additional intermediate drops.
Longer daisy chain runs from card file to card file in one cabinet can also include card files in an adjacent
cabinet. I/O Link Interface cables with the appropriate number of drops must be ordered to satisfy your
HPM subsystem configuration (number of card files).
I/O Link Interface cable shield grounding (non-CE Compliance)
Only one point along the I/O Link Interface cable daisy chain should provide ground to the cable chain
shield. This is normally done on the backpanel of the first HPMM card file (file position 1) in the first
HPM cabinet (with jumpers on the backpanel).
On a 7-Slot card file, J29 and J22 are located between the I/O Link Interface cable connectors. Both the
A and B I/O Link Interface cables have their own jumper for grounding the cable shield. J29 is for the A
cable shield and J22 is for the B cable shield. The cable shield is grounded if the jumper is bridged across
both pins.
On the 15-Slot card file, J44 and J45 are located between the I/O Link Interface cable connectors and
accomplish the same function.
The above I/O Link Interface cable shield grounding must be carefully adhered to when installing or
upgrading a High-Performance Process Manager subsystem. Failure to follow the above guidelines can
result in unwanted ground loops and abnormal system sensitivity to RFI and ESD influence from the
surrounding environment.
I/O Link Interface cable shield grounding (CE Compliance)
CE Compliance requires that the I/O Link Interface cable shield be grounded to the card file chassis
(Safety Ground) at each connector. This is accomplished with shield wire that attaches to a FASTON
terminal on the card file's backpanel ground plate. Only cables with a part number of 51204042-xxx can
be used. See the
High-Performance Process Manager Installation manual for additional information.
Induced power surge protection
An induced power surge of 10 amperes or greater can originate through an FTA’s field connections as a
result of a lighting strike and elevate the card file(s) above the common mode range of the HPM’s I/O
Link Interface transceivers and cause transceiver failure.
To prevent this occurrence, a power cable was developed with a surge protection network that filters the
power surge on the I/O Link Interface to the power cable’s ground before the I/O Link Interface connects
to the card file.It illustrates a pair of surge protection network power cables, cable A and cable B.
The I/O Link Interface connects to the surge protection network that is an integral part of the power
cable, passes through the filter, and then connects to the card file. The method of implementing the surge
protection is illustrated in the following figures.