Honeywell30735680-501Analog I/O Printed Wiring Board for DCP 7700 Ramp/Soak Programmer Controller

Product Description

What this part is

This is a Honeywell 30735680-501 analog I/O printed wiring board — the internal analog card from a DCP 7700 Digital Control Programmer. It handles the instrument’s analog input conditioning and its analog retransmission / control output stage. It is a board-level spare that lives inside a DCP 7700 chassis; it is not a standalone rail-mounted PLC I/O module and it does not work outside the instrument.

Decoding the part number

30735680 — the Honeywell drawing / assembly number for the analog I/O board.
-501 — the build variant suffix. Honeywell uses the -5xx range for the released production build of a printed wiring assembly; match it exactly, because -501 and other suffixes are not always jumper-compatible.
PWB / PWA — Honeywell’s own terms, printed wiring board / printed wiring assembly. Boards are catalogued under both, so both are worth searching.

What this means in practice

The DCP 7700 is a ramp/soak setpoint programmer used on furnaces, ovens, autoclaves and environmental chambers, where a recipe of temperature segments has to run unattended. When the instrument loses its process input or its retransmitted output while the display and keypad still work, the analog card is the usual culprit — which is why this board is stocked as a spare rather than a whole instrument. Swapping the card keeps the existing recipe programming, tag number and panel cutout intact.

Quantity and configuration

Priced and sold as one board. No DCP 7700 instrument, no case or bezel, no display or keypad assembly, no rear terminal block, no ribbon cabling and no documentation are included. Reuse the harness and terminal block already in your instrument.

Installation and setup notes

Isolate and lock out the instrument supply before withdrawing the chassis — a DCP 7700 sits on line voltage at the rear terminals. Handle the board by its edges: the analog front end is static sensitive and a damaged input stage shows up later as drift rather than an obvious failure. Note the position of every jumper and any input-range link on the board you are removing and replicate it on the replacement before power-up, then verify the input against a known source and re-scale the retransmission output before returning the loop to service.

Interchange guidance

Searched as 30735680-501, 30735680501, 30735680 501, 3073568-0501 and Honeywell DCP7700 analog I/O card. The DCP 7700 line is long obsolete — Honeywell’s current equivalents are the DCP 551 / DC P550 programmer range and the UDC-series controllers, none of which accept this board. That makes surplus stock and board-repair houses the practical source for keeping a DCP 7700 in service, and it is why a spare on the shelf is worth more than the list price suggests.