Eclipse Veri-Flame Single Burner Monitoring System, Model 5600, V1, Installation Guide 818, 1/15/2015
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Introduction
This section describes the proper wiring, installation and
sighting considerations for all sensors that can be used
with a Veri-Flame.
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Incorrect sensor installation may cause the sensor
to generate a false flame signal, possibly resulting
in the collection of unburned fuel in the
combustion chamber. This unburned fuel creates
the potential for explosions which can result in
injuries, death and property damage. Be certain
that the flame sensor detects acceptable pilot and
main flames only.
Sensor Wiring
Route sensor wiring a sufficient distance from ignition and
other high voltage or high current wiring to avoid electrical
interference. Interference from ground currents, nearby
conductors, radio-frequency emitters (wireless devices),
and inverter drives can induce false flame signals.
Shielded cables can help reduce interference with the
shield connected to ground at the control end only. The
wire type and its capacitance (picofarads or microfarads)
to ground may cause low signal problems, so a grounded
shield may decrease the signal due to the cable’s internal
capacitance. Multiple UV tube-type sensor leads run
together without shielding may interfere or “cross talk”, so
the shield or flexible armor must be grounded to prevent
this situation. For flame rod sensor running approximately
30 meters (100 feet) or greater, use Eclipse part number
21741 coax cable. To achieve the maximum wiring
distance, the shield should not be grounded (keep in mind
that an ungrounded shield provides less protection
against electrical interference).
NOTE:
Unshielded sensor wiring must not be run in
common with other wires; it must be run in separate
conduit. Multiple unshielded flame sensor wiring must not
be run together for long lengths in a common conduit or
wireway. Use number 14 to number 18 AWG wire suitable
for 90°C (194°F) and 600 volt insulation, or a better grade
if required by the application. Multiple shielded flame
sensor cables can be run in a common conduit.
Flame Rods
Figure 6.1. Flamerod Position
Flame rods should be used only on gas burners. They
accumulate soot from oil burners, causing nuisance
shutdowns and unsafe operating conditions.
See the burner manufacturer’s literature for flamerod
mounting location. When installing flame rods, please
consider the following:
1. Keep the flamerod as short as possible and at least
13 mm (1/2 inch) away from any refractory.
2. Position the rod into the side of both the pilot and
main flames, preferably at a descending angle to
minimize drooping of the flamerod against burner
parts, see Figure 6.1. Flamerod position must
adequately detect the pilot flame at all burner draft
conditions. Extend the rod 13 mm (1/2 inch) into
non-luminous flames, such as blue flames from
burning an air/gas mixture. For partially luminous
flames, such as atmospheric air/gas mixtures,
place the rod at the edge of the flame.
3. Provide a burner/flame grounding area that is at
least four times greater than the flamerod area
contacting the flame. The flamerod/burner ground
ratio and position of the rod in the flame may need
adjustment to yield maximum flame signal strength.
4. Ignition interference from the spark plug may
increase or decrease the flame signal strength.
Reversing the ignition transformer primary leads
may reduce this effect. Changing the spark gap or
adding grounding area between the flamerod and
spark plug may eliminate the interference.
WARNING
WRONG
Rod Detects
Weak Pilot
PILOT
CORRECT
Rod Detects
Only Strong
Pilot Flame
Sensor Installation
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