Honeywell RM7898A1018 Burner Control Modules
The Honeywell RM7898A1018, also cataloged as the RM7898A Relay Module, operates as a dedicated hardware component for microprocessor-based burner management and flame safety sequencing within 7800 Series control systems. It executes automatic burner sequencing, valve proving system (VPS) tests, ignition control, flame supervision, and safe shutdown sequences across industrial combustion equipment.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | RM7898A1018 (RM7898A) |
| Brand | Honeywell |
| Origin | USA |
| Weight | 1.36 kg (3.00 lbs) |
| Dimensions | 127 mm x 127 mm x 60 mm |
| Operating Temp | -40 to 60 deg C |
| Power Consumption | 120 VAC (+10/-15%), 50/60 Hz (10 VA max) |
| Module Type | Primary Burner Control Relay Module |
| Features | Integrated VPS, Selectable Pilot Type, Early Spark Termination |
| Timing Functions | Preignition, 4 s or 10 s Pilot Flame Establishing Period (PFEP) |
| Interlocks | Selectable Running Interlocks |
| System Family | 7800 Series Burner Controls |
4-20 mA HART Loop Protocol Integration and Channel-to-Channel Isolation
Engineered for safety-critical combustion monitoring, the RM7898A1018 utilizes isolated internal signal buses and optically decoupled inputs to protect core microprocessors from high-voltage ignition transients and field contact noise. Internal logic circuits enforce strict channel-to-channel isolation between low-voltage flame signal processing circuits and 120 VAC switching output lines. When installed in integrated burner control panels alongside temperature loop controllers using 4-20 mA HART loop protocol transmitters or cold junction compensation (CJC) thermocouple interfaces, the module maintains high noise immunity and prevents high-frequency line interference from affecting flame signal detection threshold levels.
Frequently Asked Questions
Q: What function does the integrated Valve Proving System (VPS) perform on the RM7898A1018?
A: The VPS automatically verifies the tightness of safety shutoff valves before burner startup or immediately after burner shutdown, locking out the system if fuel gas leakage is detected.
Q: Can the Pilot Flame Establishing Period (PFEP) timing be adjusted in the field?
A: Yes. The PFEP timing is configurable for either a 4-second or 10-second period using selectable site options on the module or through configuration software.
Field Installation Guidelines
- Disconnect all 120 VAC power sources from the burner control cabinet prior to mounting or servicing the relay module.
- Align the rear terminal header pins of the RM7898A1018 with the standard 7800 Series subbase (Q7800) chassis socket.
- Push the module firmly onto the subbase until the top and bottom retaining screws align with the subbase threaded inserts, then tighten securely.
- Ensure all field wiring, including safety interlocks, fuel valves, and ignition transformers, is connected according to the wiring diagram on the subbase.
- Connect the flame detector signal lead wire directly to the designated subbase terminals using shielded cable to minimize electrical noise interference.
Honeywell RM7898A1018 Burner Control Modules
Honeywell RM7898A1018 Burner Control Modules
The Honeywell RM7898A1018, also cataloged as the RM7898A Relay Module, operates as a dedicated hardware component for microprocessor-based burner management and flame safety sequencing within 7800 Series control systems. It executes automatic burner sequencing, valve proving system (VPS) tests, ignition control, flame supervision, and safe shutdown sequences across industrial combustion equipment.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | RM7898A1018 (RM7898A) |
| Brand | Honeywell |
| Origin | USA |
| Weight | 1.36 kg (3.00 lbs) |
| Dimensions | 127 mm x 127 mm x 60 mm |
| Operating Temp | -40 to 60 deg C |
| Power Consumption | 120 VAC (+10/-15%), 50/60 Hz (10 VA max) |
| Module Type | Primary Burner Control Relay Module |
| Features | Integrated VPS, Selectable Pilot Type, Early Spark Termination |
| Timing Functions | Preignition, 4 s or 10 s Pilot Flame Establishing Period (PFEP) |
| Interlocks | Selectable Running Interlocks |
| System Family | 7800 Series Burner Controls |
4-20 mA HART Loop Protocol Integration and Channel-to-Channel Isolation
Engineered for safety-critical combustion monitoring, the RM7898A1018 utilizes isolated internal signal buses and optically decoupled inputs to protect core microprocessors from high-voltage ignition transients and field contact noise. Internal logic circuits enforce strict channel-to-channel isolation between low-voltage flame signal processing circuits and 120 VAC switching output lines. When installed in integrated burner control panels alongside temperature loop controllers using 4-20 mA HART loop protocol transmitters or cold junction compensation (CJC) thermocouple interfaces, the module maintains high noise immunity and prevents high-frequency line interference from affecting flame signal detection threshold levels.
Frequently Asked Questions
Q: What function does the integrated Valve Proving System (VPS) perform on the RM7898A1018?
A: The VPS automatically verifies the tightness of safety shutoff valves before burner startup or immediately after burner shutdown, locking out the system if fuel gas leakage is detected.
Q: Can the Pilot Flame Establishing Period (PFEP) timing be adjusted in the field?
A: Yes. The PFEP timing is configurable for either a 4-second or 10-second period using selectable site options on the module or through configuration software.
Field Installation Guidelines
- Disconnect all 120 VAC power sources from the burner control cabinet prior to mounting or servicing the relay module.
- Align the rear terminal header pins of the RM7898A1018 with the standard 7800 Series subbase (Q7800) chassis socket.
- Push the module firmly onto the subbase until the top and bottom retaining screws align with the subbase threaded inserts, then tighten securely.
- Ensure all field wiring, including safety interlocks, fuel valves, and ignition transformers, is connected according to the wiring diagram on the subbase.
- Connect the flame detector signal lead wire directly to the designated subbase terminals using shielded cable to minimize electrical noise interference.
