Cleaver-Brooks CB780 - Environmental Ratings; Weight; Flame Detection Systems; Sequence Timing for Normal Operation

750-166 1-3
CB780/CB784
SPECIFICATIONS
ENVIRONMENTAL RATINGS:
Ambient Temperature:
Operating: -40°F to 140°F.
Storage: -40°F to 150°F.
Humidity: 85% RH continuous, noncondensing.
Vibration: 0.5G environment.
DIMENSIONS: Refer to Figs. 1 and -2.
WEIGHT:
CB780/CB784: 1 pound 10 ounces, unpacked.
Keyboard Display Module: 4 ounces, unpacked.
IMPORTANT: Flame Detection System available for use
with CB780/CB784. To select your Plug-in Flame
Signal Amplifier and matching Flame Detector, see
Table 2.
TABLE 2—FLAME DETECTION SYSTEMS (FIGS. 3, 4, 5).
a
The 817-1743 Flame Detector should be used only on burners that cycle on-off at least once every twenty-four hours. Appliances with
burners that remain on for twenty-four hours continuously or longer should use the 817-1121 Flame Detector with the 833-2741 Amplifier
as the ultraviolet flame detection system.
b
Circuitry tests all electronic components in the flame detection system (amplifier and detector) 12 times a minute during burner operation
and shuts down the burner if the detection system fails.
c
Circuitry tests the flame signal amplifier 12 times a minute during burner operation and shuts down the burner if the amplifier fails.
TABLE 3—SEQUENCE TIMING FOR NORMAL OPERATION.
2
Flame
Establishing
Period
Post
Purge Interlock
Firing
Rate
Energy
Saving
Approval
Code
Device Initiate Standby Purge Pilot Main Run
Timing Circuits Circuit Prepurge Bodies
CB 780/
CB 784
10 sec * ** 4 or
10 sec
10 or
15 sec
1
* 15 sec Preignition,
Lockout,
High and
Low Fire
4-wire
modulating
No FM/IRI
Modulating
* STANDBY and RUN can be an infinite time period.
** PURGE will be determined by which purge card is selected.
1
The MFEP will be determined by which terminal is used, see Figs. 7 and 18.
2
The operating sequence of the CB780 and CB784 Relay Modules are identical. The only difference between the Relay
Modules is that the Keyboard Display Module is standard with the CB780 and optional with the CB784.
APPROVAL BODIES:
Underwriters Laboratories Inc. listed, File No. MP268,
Guide No. MCCZ.
Canadian Standards Association certified, LR9S329-3.
Factory Mutual approved, Report No. JI1V9A0.AF.
IRI acceptable.
Federal Communications Commission, Part 15, Class B—
Emissions.
Plug-In Flame Amplifiers Applicable Flame Detectors
Type Color Self-Checking
Part
Number
Flame
Failure
Response
Time Fuel Type
Part
Number
Infrared Red No 833-2722 3 sec. Gas, oil,
coal
Infrared
(Lead Sulfide)
817-1742
Dynamic AMPLI-
CHECK™
833-2723
c
Gas, oil,
coal
Infrared
(Lead Sulfide)
817-1742
Ultraviolet Purple No 833-2724 Gas, oil Ultraviolet 817-1743
a
Ultraviolet
Self-Check
Green Dynamic Self-
Check
833-2741
b
Gas, oil,
coal
Ultraviolet
(Purple
Peeper)
817-1121
Dynamic Auto-Check