HIMA F8652X Central Module | HIQuad H41q Safety Controller CPU

Description

Core Product Summary

The HIMA F8652X is a safety-related central module (CPU) from HIMA Paul Hildebrandt GmbH for the PES H41q programmable electronic safety system, used in the -MS, -HS, and -HRS configurations. It executes the safety-related user program and controls the I/O and communication modules of the H41q system. In redundant H41q-HRS systems, two F8652X central modules operate in parallel in the central rack.

The module runs on two clock-synchronized Intel 386EX 32-bit microprocessors at 25 MHz. Each microprocessor has 1 MByte of Flash-EPROM for the operating system, 1 MByte of Flash-EPROM for the user program, and 1 MByte of SRAM for data. The module provides two RS-485 serial interfaces, a four-digit matrix diagnostic display with requestable information, and a fail-safe watchdog with a 24 V DC output loadable up to 500 mA and short-circuit proof. It requires 8 TE of rack space and draws 5 V DC at 2000 mA. The F8652X covers safety requirement classes AK 1–6 and operates within the H41q system context certified up to SIL 3 per IEC 61508.

Key Technical Specifications

Detailed Product Overview

In a PES H41q controller, the F8652X is the module that runs the safety logic. Its core design principle is the 1oo2D arrangement: two Intel 386EX microprocessors process the same user program clock-synchronized at 25 MHz, and their results are compared. A fault detected in either channel switches off the watchdog signal of the central module and therefore its outputs — the system goes to the safe state rather than executing on a possibly corrupted result. Within the H41q family, this architecture underpins the AK 1–6 classification and the TÜV certification of the systems up to SIL 3 per IEC 61508.

The memory layout is generous for this platform generation: each microprocessor carries its own 1 MByte Flash-EPROM for the operating system, 1 MByte Flash-EPROM for the user program, and 1 MByte of SRAM for variables. Because both processors execute identical copies of the program, the effective program size limit is the per-processor 1 MByte, which positions the F8652X as the memory-extended member of the H41q central module line. HIMA documentation states that the F8652X can be used to replace the earlier F 8652, F 8652A, and F 8652E modules, which makes it the practical choice when a defective older central module has to be replaced and the user program exceeds the memory of the original units.

The data memory is battery-backed. The buffer battery is a lithium cell (e.g. type CR 2477N, HIMA part no. 44 0000018) with its own measuring circuit and a BATI display indication. Its expected lifetime without external voltage feeding is 1000 days at 25 °C ambient and 200 days at 60 °C; HIMA recommends replacement at the latest after six years, or within three months after the BATI indication appears. This maintenance item is one of the few periodic tasks on the central module and should be part of the plant’s spare-parts and service plan.

Local diagnostics use the four-digit matrix display on the module front, from which a technician can request status and fault information directly at the rack. The two RS-485 interfaces handle serial communication, including the connection to the PADT engineering PC. For Ethernet-based communication — ELOP II TCP, safeethernet, and Modbus TCP — the H41q system uses the F 8627X communication module, reached by the central module over the backplane bus; optional F 8621A coprocessor modules extend communication processing.

For integration planning, the F8652X requires 8 TE of rack space and draws 2000 mA at 5 V DC. In redundant H41q-HRS configurations, the system kits pair two F8652X central modules in the central rack — for example, the H41q-HRS B 4237-2 assembly kit contains two F 8652X central modules along with the power supply, monitoring, decoupling, fan, and bus termination modules of the rack. Both the slot budget and the doubled 5 V load of two central modules must be considered when configuring or servicing such a rack.

F8652X

F8652X

System Compatibility & Integration Requirements

Engineering Selection Highlights

• System fit: The F8652X is the central module for PES H41q-MS, -HS, and -HRS; it does not belong to the H51q or HIMax platforms and is selected for H41q-based installations.
• Safety scope: Requirements class AK 1–6, within H41q systems TÜV certified up to SIL 3 per IEC 61508 — match the module choice against the application’s required safety integrity level in the system documentation.
• Memory capacity: 1 MByte user program and 1 MByte SRAM per microprocessor — the extended-memory option in this central module line, relevant for larger safety programs.
• Replacement of older central modules: HIMA documentation identifies the F8652X as usable in place of the F 8652, F 8652A, and F 8652E; verify the installed operating system version and configuration when planning such a replacement.
• Power and space budget: 8 TE and 2000 mA at 5 V DC per module; redundant H41q-HS/HRS racks with two central modules need double this budget.
• Battery maintenance: Retained data depends on a lithium buffer battery; plan replacement at the latest after six years, or within three months of the BATI display indication.
• Communication architecture: Serial access via the two RS-485 interfaces; Ethernet communication (ELOP II TCP, safeethernet, Modbus TCP) requires the F 8627X communication module over the backplane bus.

FAQ

What is the HIMA F8652X?
The F8652X is a safety-related central module (CPU) for HIMA PES H41q-MS, H41q-HS, and H41q-HRS safety controllers, executing the safety-related user program.

How does the F8652X process the safety program?
It uses two clock-synchronized Intel 386EX microprocessors at 25 MHz whose results are compared; a detected fault switches off the module’s watchdog signal and outputs, driving the system to the safe state.

How much memory does the F8652X have?
Each microprocessor carries 1 MByte of Flash-EPROM for the operating system, 1 MByte of Flash-EPROM for the user program, and 1 MByte of SRAM for data.

Which safety level does it cover?
The module is classified for requirement classes AK 1–6 and is used in H41q systems that are TÜV certified and applicable up to SIL 3 per IEC 61508.

Can the F8652X replace older central modules?
Yes. HIMA documentation states that the F8652X can be used to replace the earlier F 8652, F 8652A, and F 8652E modules; the on-site configuration should be verified as part of the change.

What battery does the F8652X use and when must it be changed?
It uses a lithium buffer battery (e.g. type CR 2477N, HIMA part no. 44 0000018) with an expected lifetime of 1000 days at 25 °C or 200 days at 60 °C without voltage feeding; HIMA recommends replacement at the latest after six years, or within three months of the BATI display indication.

How is the F8652X connected for engineering and communication?
Serial access uses the two RS-485 interfaces; Ethernet communication (ELOP II TCP, safeethernet, Modbus TCP) runs through the F 8627X communication module via the backplane bus.

How much rack space and power does the module need?
The F8652X requires 8 TE of rack space and draws 2000 mA at 5 V DC from the rack supply.

Verification & Troubleshooting Notes

• Fault indicated on the module: Use the four-digit matrix display to request the diagnostic information before taking action; the operating-system documentation of the H41q system contains the error code lists and their meanings.
• BATI display appears: This is the battery indication — replace the buffer battery within three months; the recommended maximum service interval is six years regardless of indication. The battery can be changed with the CPU in operation.
• Communication failure over RS-485: Check the bus station number and transmission rate settings at switch S1 on the module against the network configuration; a mismatch here is a primary cause of serial communication faults.
• No Ethernet connectivity: The F8652X has no Ethernet ports; verify that the F 8627X communication module is installed and seated correctly, since Ethernet traffic runs via the backplane bus.
• Central module does not start after replacement: When replacing an F 8652, F 8652A, or F 8652E with the F8652X, confirm the operating system version loaded on the module matches the system configuration before power-up.
• Rack power issues: The module draws 2000 mA at 5 V DC; in redundant racks verify the power supply modules can support two central modules plus the communication and coprocessor modules.
• Watchdog output inactive: The fail-safe watchdog output (24 V DC, up to 500 mA) switches off on detected faults; identify the underlying fault via the diagnostic display rather than forcing the output.
• All work on the safety system must follow the HIMA operating system manual and safety manual for H41q/H51q and the plant’s safety procedures; do not bypass watchdog or comparison functions.