
750-166 1-1
Section 1 - CB780/CB784
Installation and Operating Instructions
—Flame signal strength.
—Expanded annunciator status.
—Total cycles of operation.
—Total hours of operation.
—Fault history of six most recent faults:
• Cycles of operation at time of fault.
• Expanded annunciator data at time of fault.
• Fault message and code.
• Hours of operation at time of fault.
• Sequence status at time of fault.
• Sequence time at time of fault.
—Diagnostic information:
• Device type.
• Flame amplifier type.
• Flame failure response time.
• Manufacturing code.
• On/Off status of all digital inputs and outputs.
• Selected prepurge time.
• Software revision and version of CB780/CB784 and
Keyboard Display Module.
• Status of configuration jumpers.
• Status of Run/Test Switch.
CONTENTS
Specifications ............................................................... 2
Principle Technical Features ...................................... 6
Safety Provisions ......................................................... 7
Installation ................................................................... 9
Wiring ........................................................................ 11
Assembly .................................................................... 15
Operation ................................................................... 18
Static Checkout .......................................................... 25
Checkout .................................................................... 27
Troubleshooting ......................................................... 34
—Interlock check.
—Closed loop logic test.
—Dynamic Auto-Check.
—Dynamic input check.
—Dynamic safety relay test.
—Dynamic self-check logic.
—Expanded safe-start check.
—High Fire Purge Switch test.
—Internal hardware status monitoring.
—Low Fire Start Switch test.
—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-outannunciationandsystem diagnosticsprovided by
a2 rowby20 columnVacuumFluorescentDisplay(VFD)
located on the Keyboard Display Module.
■First-out expanded annunciation with 26 Light Emitting
Diodes (LEDs) for limits and interlocks (optional).
■FivesequenceinformationLightEmittingDiodes(LEDs).
■Five function Run/Test Switch.
■Interchangeable plug-in flame amplifiers.
■Local or remote annunciation of operation and fault
information.
■Nonvolatilememory forretaininghistoryfilesand sequenc-
ing status after loss of power.
■Remote reset (optional).
■Report generation (optional).
■Burner controller data:
—Sequence status.
—Sequence time.
—Hold status.
—Lockout/alarm status.
The Cleaver-Brooks CB780/CB784 is a microprocessor
based integrated burner control for automatically fired
gas, oil, or combination fuel single burner applications. The
CB780 consists of a Relay Module and Keyboard Display
Module. The CB784 consists of the Relay Module only. The
Keyboard Display Module is optional with the CB784. Sub-
base, Amplifier, and Purge Card are required to complete the
system. Options include Personal Computer Interface, Control
Bus, Remote Display Mounting, First-Out Expanded Annun-
ciator and Combustion System Managment software.
The CB780/CB784 is programmed to provide a level of
safety, functional capability and features beyond the capacity
of conventional controls.
Functions provided by the CB780/CB784 include auto-
matic burner sequencing, flame supervision, system status
indication, system or self-diagnostics and troubleshooting
.
■Safety features: