7800 SERIES RM7890A,B,C
The Honeywell RM7890 is a microprocessor
based integrated burner control for automatically
fired gas, oil or combination fuel single-burner appli-
cations. The RM7890 consists of the Relay Module.
Subbase and Amplifier are required to complete the
system. Options include Keyboard Display
Module, Personal Computer Interface, DATA
CONTROLBUS MODULE™, Remote Display Mod-
ule, First-Out Expanded Annunciator and COM-
BUSTION SYSTEM MANAGER™ Software.
The RM7890 is programmed to provide a level of
safety, functional capability and features beyond the
capacity of conventional controls.
Functions provided by the RM7890 include auto-
matic burner sequencing, flame supervision, system
status indication, system or self-diagnostics and
troubleshooting.
Safety features:
- Closed loop logic test.
- Dynamic AMPLI-CHECK™.
- Dynamic input check.
- Dynamic safety relay test.
- Dynamic self-check logic.
- Expanded safe-start check.
- Internal hardware status monitoring.
- Tamper resistant timing and logic.
Access for external electrical voltage checks.
Application flexibility.
Communication interface capability.
Dependable, long-term operation provided by microcom-
puter technology.
First-out annunciation and system diagnostics are provided
by a 2 row by 20 column Vacuum Fluorescent Display
(VFD) located on the optional Keyboard Display Module.
First-out expanded annunciation with 26 Light Emitting
Diodes (LEDs) for limits and interlocks (optional).
Five (LEDs) for sequence information.
Interchangeable plug-in flame amplifiers.
Local or remote annunciation of RM7890 operation and fault
information (optional).
Nonvolatile memory; RM7890 retains history files and
sequencing status after loss of power.
Remote reset (optional).
Report generation (optional).
Selectable relight or lockout on loss of flame.
Shutter drive output (RM7890B).
Burner controller data (optional):
- Expanded annunciator status.
- Flame signal strength.
- Hold status.
- Lockout/alarm status.
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- Sequence status.
- Sequence time.
- Total cycles of operation.
- Total hours of operation.
- Fault history providing the six most recent faults:
• Cycles of operation at the time of the fault.
• Expanded annunciator data at the time of the fault.
• Fault message and code.
• Hours of operation at the time of the fault.
• Sequence status at the time of the fault.
• Sequence time at the time of the fault.
- Diagnostic information:
• Device type.
• Flame amplifier type.
• Flame failure response time.
• Manufacturing code.
• On/Off status of all digital inputs and outputs.
• Software revision and version of RM7890 and op-
tional Keyboard Display Module.
• Status of configuration jumpers.
CONTENTS
Installation ..................................................... 9
Wiring .......................................................... 11
Assembly ...................................................... 13
Operation ..................................................... 15
Checkout ...................................................... 19
G. R. • Rev. 2-94 • © Honeywell Inc. 1994 • Form Number 65-0126-2
1
Relay Module
65-0126-2