The HIMA F8621A (part number 984862160) is a Coprocessor Module (often referred to as a Communication or CPU Module) designed for use in HIMA H51q (HIQuad) safety systems.

It functions as a secondary processing unit to offload tasks from the central module, specifically handling intensive communication protocols and data processing to maintain high system performance in SIL 3 safety environments.

Core Technical Specifications

Z7306
BV7046-4
K9202B
X-FAN 18 03
F8620/11
ELOPII
F7131 981713102
F8621A 984862160

Key Features

Dual-Port RAM: Includes a dedicated Dual-Port RAM area which allows for extremely fast data exchange with the second central module in redundant configurations.

Battery Buffering: The RAM is buffered against power loss via the F7131 module (which we discussed earlier), ensuring that critical project data and variables are not lost during a system restart.

F8621A

Isolation: The RS-485 interfaces feature galvanic isolation, protecting the internal electronics of the module from electrical noise or surges originating in the field wiring.

Safety Integration: Fully compatible with the SILworX programming tool for configuration and validation within a safety loop.

Comparison: F8621 vs. F8621A

F8621A

The “A” suffix in F8621A usually denotes a hardware revision or a specific firmware capability update over the original F8621.

In most legacy H51q systems, the F8621A is a drop-in replacement for older versions, though you should always verify the firmware compatibility with your existing Central Module (e.g., F8650).

Maintenance Note

If you are replacing this module, remember that the communication parameters (like Station ID and Baud Rate) are often defined by S1–S4 DIP switch settings or within the system software.  Be sure to document the switch positions on the old module before removing it.