8
£
8.
Proven types of flame grounding adapters, as shown below, may be used to provide adequate
grounding surface. High temperature stainless steel should be used to minimize the effect of
metal oxidation. This assembly may be welded directly over the pilot or main burner nozzle
WIRING OF FLAME RODS
For proper operation of flame rectification systems (flame rods), it is necessary to maintain at least
20 megohms insulating resistance in the flame rectification circuit.
1.
The scanner should be wired using metal cable or rigid conduit.
2.
High voltage wiring must not be installed in the same conduit with scanner wiring.
Selection of Scanner Wire
1.
Use #14, 16, or 18 gauge wire with 90
q
C, 600 volt insulation for up to 100 feet (30M) distance.
2.
The type of insulation used with flame rectification wiring is important, since it must protect
against current leakage resistance to ground. Use Belden 8254-RG62 Coaxial Cable (or equal)
for runs greater than 100 feet (30M).
Maximum wiring run not to exceed 400 feet (120M).
MAINTENANCE
Type UV1, UV2, UV8A, and 45UV3 Ultraviolet Scanners
The viewing area of the scanner must be kept clean. Even a small amount of contamination will
reduce the flame signal reaching the detector by a measurable amount. Wipe the viewing area rou-
tinely using a soft cloth dampened with concentrated detergent.
Type 69ND1 Flame Rod
The flame rod and its insulator should be kept clean by washing routinely with soap and water. Rods
should be routinely replaced as they oxidize.
Flame Signal Strength
Routine observation of the flame signal strength will forewarn any deterioration in the capability of
the flame detector or its application.
Periodic Safety Check
It is recommended that a procedure be established to test the complete flame safeguard system at
least once a month. This test should verify the proper operation of all limit switches and safety inter-
locks as well as flame failure protection and fuel safety shutoff valve tightness.
Rotation
It is recommended that control and scanner units purchased as spares be installed periodically.
BOMB FIN
GROUNDING
ASSEMBLY
THREADED ROD
ASSEMBLY
