CleaverBrooks CB780 User Manual

INSTALLATION INSTRUCTIONS
32-00207-01
SIL
3
Capable
CB780/CB784
Relay Modules
APPLICATION
The Cleaver-Brooks CB780/CB784 (833-2718/833-
2720)
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. Subbase, Amplifier,
and Purge Card are required to complete the system.
Options include DATA CONTROLBUS MODULE™*, Remote
Display Mounting, First-Out Expanded Annunciator or
Modbus™ Module.
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
automatic burner sequencing, flame supervision, system
status indication, system or self-diagnostics and
troubleshooting
FEATURES
• Safety features:
— Interlock check.
— Closed loop logic test.
— Dynamic AMPLI-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 using Modbus Module
833-2820.
• Dependable, long-term operation provided by
microcomputer technology.
• First-out annunciation and system diagnostics
provided by a 2 row by 20 column Vacuum
Fluorescent Display (VFD) located on the Keyboard
Display Module (Optional on CB784).
Contents
Application ..................................................................................... 1
Features .......................................................................................... 2
Specifications ............................................................................... 2
Principal Technical Features .................................................. 6
Safety Provisions ......................................................................... 6
Installation ..................................................................................... 7
Wiring ............................................................................................... 10
Assembly ......................................................................................... 13
Operation ........................................................................................ 17
Static Checkout ............................................................................ 26
Troubleshooting ........................................................................... 26

CleaverBrooks CB780 Specifications

General

Brand	CleaverBrooks
Model	CB780
Category	Relays
Language	English

Summary

APPLICATION

FEATURES

INSTALLATION INSTRUCTIONS

SPECIFICATIONS

PRINCIPAL TECHNICAL FEATURES

Safety Provisions

Details the conditions under which safety shutdowns (lockouts) occur.

Internal Hardware Status Monitoring

Explains how the CB780/CB784 checks its internal hardware integrity.

Closed Loop Logic Test

Describes the test verifying the integrity of safety critical loads.

INSTALLATION

Wiring Information

Details wiring connections, compliance with codes, and recommended wire size and type.

ASSEMBLY

Relay Module Mounting

Guidance on vertically or horizontally mounting the CB780/CB784 unit.

Installing the Purge Card

Steps for removing the old purge card and inserting a new one.

OPERATION

Sequence of Operation

Details the step-by-step burner sequence the CB780/CB784 follows.

INITIATE

Explains the initial sequence state upon power application or voltage fluctuations.

STANDBY

Describes the state where the control is ready to start an operating sequence.

NORMAL START-UP PREPURGE

Details the PREPURGE timing and conditions for starting the sequence.

STATIC CHECKOUT

Selectable Site-Configurable Jumpers

Explains jumper options for configuring PFEP and Interlock Check.

General Instructions

Outlines general steps and precautions for performing checkout tests.

Flame Signal Measurement

Preliminary Inspection

Checks wiring, detector cleanliness, amplifier/detector combination, and secure component seating.

Initial Lightoff Check for Proved Pilot

Pilot Turndown Test

Hot Refractory Hold-in Test

Ultraviolet Sensor, Ignition Spark Response Test

Safety Shutdown Tests

TROUBLESHOOTING

CB780/CB784 System Diagnostics

Explains how self-diagnostics and first-out annunciation aid in troubleshooting.

Diagnostic Information Index

Historical Information Index

SAFETY AND SECURITY

Physical device protection

Recommendations for securing the device from unauthorized access and tampering.

Modbus & DDL Interface security

Guidance on protecting device functionality and interface protocols.