Honeywell RM7850A1001 Burner Control Relay
The Honeywell RM7850A1001, also cataloged as the RM7850 burner control module, operates as a dedicated hardware component for sequential combustion programming and European Community timing execution within 7800 Series burner management architectures.
Suffix Breakdown & Model Matrix
- RM7850: Designates the 7800 Series microprocessor-based burner control relay module platform configured for European Community timing standards.
- A: Identifies the base programming control logic variant featuring lockout interlocks and interrupted pilot operation.
- 1001: Specifies the exact hardware configuration variant incorporating a 0.2 s post-purge cycle, user-selectable airflow check, and 120 VAC operational rating.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | RM7850A1001 |
| Brand | Honeywell |
| Origin | United States |
| Weight | 3.00 lbs |
| Dimensions | Standard 7800 Series plug-in enclosure profile |
| Operating Temp | -40 deg C to +60 deg C |
| Power Consumption | 120 VAC (+10%, -15%), 50/60 Hz, 25 VA max |
| Series Type | 7800 Series European Community Relay Module |
| Pilot Configuration | Interrupted pilot type with intermittent second-stage pilot valve |
| Post-Purge Interval | 0.2 s post-purge cycle |
| Airflow Verification | User-selectable airflow check switch |
Channel-to-Channel Isolation and Loop Integrity
The unit enforces strict channel-to-channel isolation across internal relay outputs, valve drivers, and safety interlock circuits to prevent ground loops and common-mode electrical interference. Operating on standard industrial power rails, the circuitry integrates robust filtering and signal conditioning to validate flame detector inputs against spurious electromagnetic noise. The internal architecture maintains deterministic response timings for running interlocks, ignition trials, and European Community compliant purge cycles without signal degradation.
Frequently Asked Questions
Q: What is the specific post-purge duration executed by the RM7850A1001 module?
A: The RM7850A1001 executes a rapid 0.2 s post-purge cycle upon burner shutdown to meet specific European Community operational timing requirements.
Q: Can this relay module be hot-swapped in an active industrial control panel?
A: No. Power must be entirely disconnected from the base subbase before inserting or removing the RM7850A1001 module to prevent electrical arcing and damage to terminal pins.
Q: How does the module handle airflow verification prior to ignition?
A: The unit utilizes a user-selectable airflow check function that forces the control logic to verify that combustion air proving switch contacts transition correctly before initiating trial for ignition.
Field Installation Guidelines
- Ensure main AC supply power is completely locked out and tagged out before accessing the burner management panel or subbase wiring.
- Verify that the Q7800 subbase wiring conforms to local electrical codes, utilizing shielded cable for flame signal wiring to minimize electrical noise pickup.
- Mount the unit vertically on the designated subbase, securing the chassis retention screw to maintain reliable electrical pin engagement and mechanical stability against continuous operational vibration.
- Inspect all running interlock inputs, limit switches, and safety pressure switches for proper electrical continuity before initiating a cold start verification test.
Honeywell RM7850A1001 Burner Control Relay
Honeywell RM7850A1001 Burner Control Relay
The Honeywell RM7850A1001, also cataloged as the RM7850 burner control module, operates as a dedicated hardware component for sequential combustion programming and European Community timing execution within 7800 Series burner management architectures.
Suffix Breakdown & Model Matrix
- RM7850: Designates the 7800 Series microprocessor-based burner control relay module platform configured for European Community timing standards.
- A: Identifies the base programming control logic variant featuring lockout interlocks and interrupted pilot operation.
- 1001: Specifies the exact hardware configuration variant incorporating a 0.2 s post-purge cycle, user-selectable airflow check, and 120 VAC operational rating.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | RM7850A1001 |
| Brand | Honeywell |
| Origin | United States |
| Weight | 3.00 lbs |
| Dimensions | Standard 7800 Series plug-in enclosure profile |
| Operating Temp | -40 deg C to +60 deg C |
| Power Consumption | 120 VAC (+10%, -15%), 50/60 Hz, 25 VA max |
| Series Type | 7800 Series European Community Relay Module |
| Pilot Configuration | Interrupted pilot type with intermittent second-stage pilot valve |
| Post-Purge Interval | 0.2 s post-purge cycle |
| Airflow Verification | User-selectable airflow check switch |
Channel-to-Channel Isolation and Loop Integrity
The unit enforces strict channel-to-channel isolation across internal relay outputs, valve drivers, and safety interlock circuits to prevent ground loops and common-mode electrical interference. Operating on standard industrial power rails, the circuitry integrates robust filtering and signal conditioning to validate flame detector inputs against spurious electromagnetic noise. The internal architecture maintains deterministic response timings for running interlocks, ignition trials, and European Community compliant purge cycles without signal degradation.
Frequently Asked Questions
Q: What is the specific post-purge duration executed by the RM7850A1001 module?
A: The RM7850A1001 executes a rapid 0.2 s post-purge cycle upon burner shutdown to meet specific European Community operational timing requirements.
Q: Can this relay module be hot-swapped in an active industrial control panel?
A: No. Power must be entirely disconnected from the base subbase before inserting or removing the RM7850A1001 module to prevent electrical arcing and damage to terminal pins.
Q: How does the module handle airflow verification prior to ignition?
A: The unit utilizes a user-selectable airflow check function that forces the control logic to verify that combustion air proving switch contacts transition correctly before initiating trial for ignition.
Field Installation Guidelines
- Ensure main AC supply power is completely locked out and tagged out before accessing the burner management panel or subbase wiring.
- Verify that the Q7800 subbase wiring conforms to local electrical codes, utilizing shielded cable for flame signal wiring to minimize electrical noise pickup.
- Mount the unit vertically on the designated subbase, securing the chassis retention screw to maintain reliable electrical pin engagement and mechanical stability against continuous operational vibration.
- Inspect all running interlock inputs, limit switches, and safety pressure switches for proper electrical continuity before initiating a cold start verification test.
