12
£
Safety Shutdown
1.
If pilot flame is not detected during the 10 second pilot trial-for-ignition period, the pilot valve
and ignition transformer will be deenergized and the control will lockout on safety.
2.
If flame is not detected at the end of the 10 second main flame trial-for-ignition period, all fuel
valves will be deenergized and the control will lockout on safety.
3.
If the main flame fails during a firing cycle, all fuel valves will be deenergized within four sec-
onds after loss of flame signal and the control will lockout on safety.
4.
Manual reset is required following any safety lockout.
Description of Functions of Operating Controls
1.
Operating Controls.
Generally pressure or temperature activated. Normally, when the operat-
ing control closes, the burner start-up programming starts. When the operating control opens, the
burner shuts off. They are connected between Terminals L1 and 13.
2.
Limit switches.
Generally pressure, water level or temperature activated. These devices stop the
burner when the limit switch opens and restarts it when the limit switch recloses. They are con-
nected between Terminals L1 and 13.
3.
Fuel Valve Proof of Closing Interlocks.
Generally an integral switch mounted on the main fuel
valve and activated by the valve stem. It is connected between Terminal 3 and 13. The valve
proof of closure interlock prevents a burner start-up if the valve stem is not in the
valve closed
position.
4.
Running Interlocks.
Generally air flow switches, high and low fuel pressure switches, oil tem-
perature switches, atomizing medium pressure switches, and excess smoke density controls.
These interlocks prove proper conditions for normal operation of the burner. They are connected
between Terminals 3 and P.
5.
Low Fire Start Interlocks.
Usually a firing rate motor linkage position switch, or a damper
position switch, that prove the linkage and dampers are in their proper position for burner light
off. They are connected between terminals M and D.
FIGURE 1.
PROGRAMMING SEQUENCE CHART, SERIES D30
PREPURGE
PILOT
IGNITION
MAIN FLAME
TRIAL FOR
IGNITION
TRIAL FOR
FIRING PERIOD
POST PURGE
LIMIT AND OPERATING CONTROLS CLOSED (L1-13)
FUEL VALVE PROOF OF CLOSURE SWITCH -
RUNNING INTERLOCKS - CLOSED (AIR FLOW, FUEL PRESSURE, ETC.) (3-P)
OPERATING
CONTROLS
AND INTERLOCKS
BURNER/BLOWER MOTOR (M)
LFS
CLOSED
(M-D)
15, 30, OR 90
5
10
10
15
PROGRAMMING
SEQUENCE
BURNER
INDICATORS
AIR FLOW
SPARK
PILOT VALVE INTERRUPTED (5)
PILOT VALVE INTERMITTENT (6)
MAIN FUEL VALVE (7)
TFI
CONTROL TYPE 70D30 WITH PROGRAMMER 71D81 - 15 SECOND PURGE
71D90 - 90 SECOND PURGE
FIREYE
(X)
71D80 - 30 SECOND PURGE
CLOSED (13-3)
IGNITION
Содержание D30 Series
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