Overview
Manuals
Legacy Identity
Start Address
Source Boundary
Features:
- Honeywell appendix identifies 620-0020 as 2K memory.
- Listed among superseded components still encountered in legacy systems.
- Four-position shorting board selects the memory starting address.
Honeywell's February 1988 IPC 620-25/35 manual identifies 620-0020 as a 2K (2,048-word) user-program memory module in an appendix covering superseded components. The document notes that such components may still be used in some applications. It states that the module stores the user control program, has a PASS self-test LED and normally occupies slot C in the 620-25 or slot E in the 620-35. The exact capacity is specific to 620-0020; it is not the total system memory capacity.
The appendix describes a four-position shorting board at the lower front of the module for setting the starting address. When more modules are used, the memory segments must be arranged in the documented sequence so the processor completes the memory scan. This older method differs from the DIP-switch arrangement described for later memory models in the manual. Before removal, obtain a verified program backup and record every rack position, memory size, address setting and diagnostic indication. Confirm any proposed successor using the full Honeywell compatibility table and site engineering record. After service, restore the approved program and test affected control logic.
The 620-0020 Honeywell Legacy IPC 620 2K Program Memory Module may still be available for purchase and support from Moore Automated Company beyond End-Of-Life (EOL) by the manufacturer (OEM).
Honeywell 620-0020 documentation and product links.
The product record is provided as the internal reference when an exact-model manufacturer PDF has not yet been verified.
The manufacturer appendix lists 620-0020 as 2K (2,048 words) of program memory among superseded components. This older execution should not be conflated with a similarly sized later 620-002x module. Verify the actual board label, shorting board, physical connector and installed rack before procurement or replacement.
Honeywell describes a four-position shorting board on the front of this legacy memory module. It selects the starting address within the controller's memory configuration. The manual's table shows approved sequences for multiple modules. Record the entire installed memory map and shorting-board positions before changing hardware, and avoid gaps or overlapping segments.
The February 1988 Honeywell manual supports exact model identity and capacity but not the current condition, revision or program contents of any stocked item. Its appendix says these components were superseded while still usable in some applications. Current replacement eligibility must be checked against the specific rack and Honeywell compatibility table; a capacity match alone is insufficient.
