CleaverBrooks CB780 User Manual

CB780/CB784 RELAY MODULES
27 32-00207—01
Table 8. Static Checkout.
Test
No.
Test
Jumpers
Volt-
meter Normal Operation
If Operation is Abnormal, Check the
Items Listed Below
WARNING
Explosion Hazard.
Can cause severe injury, death or property damage.
Make sure all manual fuel shutoff valves are closed.
IMPORTANT:
Low fuel pressure limits, if used, could be open. Bypass them with jumpers for the remaining Static Tests (if
required).
1 None 4-L2 Line voltage at terminal 4. 1. Master switch.
2. Power connected to the master
switch.
3. Overload protection (fuse, cir-
cuit breaker, etc.) has not
opened the power line.
2 None 6-L2 Line voltage at terminal 6. 1. Limits.
2. Burner controller.
3 None 20-L2 Line voltage at terminal 20. 1. Preignition interlocks.
44-5 7-L21. Burner motor (fan or blower) starts.
2. Line voltage at terminal 7 within 10 seconds.
1. Burner motor circuit.
a. Manual switch of burner
motor.
b. Burner motor power supply,
overload protection, and
starter.
c. Burner motor.
2. Running or Lockout Interlocks
(including Airflow Switch).
5 4-10 — Ignition spark (if ignition transformer is connected
to terminal 10).
1. Watch for spark or listen for
buzz.
a. Ignition electrodes are clean.
b. Ignition transformer is okay.
64-8 — 1. Ignition spark (if ignition transformer is con-
nected to terminal 8).
2. Automatic pilot valve opens (if connected to
terminal 8).
NOTE: Refer to wiring diagram of system being
tested.
1. Watch for spark or listen for
buzz.
a. Ignition electrodes are clean.
b. Ignition transformer is okay.
2. Listen for click or feel head of
valve for activation.
a. Actuator, if used.
b. Pilot valve.
7 4-21 — Same as test no. 6 for connections to terminal 8. If
using direct spark ignition, check the first stage
fuel valve(s) instead of pilot valve.
Same as test no. 6. If using direct
spark ignition, check the first stage
fuel valve(s) instead of the pilot valve.
8 4-9 — Automatic main fuel valve(s) open. If using direct
spark ignition with intermittent pilot on terminal
21, check the optional second stage fuel valve, if
used.
1. Listen for and observe operation
of the main fuel valve(s) and
actuator(s).
2. Valve(s) and actuator(s).
9 4-3 — Alarm (if used) turns on. 1. Alarm.
10 4-5 and
12-13
18-L2 Firing rate motor drives open; zero volts at terminal
18 after motor starts driving open.
1. Low Fire Start Switch.
2. Firing rate motor and trans-
former.
11 4-5 and
14-13
18-L2 Firing rate motor drives closed; line voltage at
terminal 18 after motor is in Low Fire position.
1. Low Fire Start Switch.
2. Firing rate motor and trans-
former.
12 4-5 and
12-13
19-L2 Firing rate motor drives open; line voltage at
terminal 19 after motor is in High Fire position.
1. High Fire Purge Switch.
2. Firing rate motor and trans-
former.

CleaverBrooks CB780 Specifications

General

Brand	CleaverBrooks
Model	CB780
Category	Relays
Language	English