41
®
WIRING - UV SCANNERS
To connect the scanner to the control, the UV1 Scanner is supplied with 36” or 72” of flexible cable.
The 45UV5 is supplied with four 72 lead wires. Install them in a suitable length of flexible armor
cable and connect it to the control. A conduit connector is supplied with the scanner. Connect black
wires (shutter) to terminals L1, L2; red wires (UV tube) to terminals S1, S2.
If it is necessary to extend the scanner wiring, the following instructions apply:
Scanner wires should be installed in a separate conduit. The wires from several scanners may be
installed in a common conduit.
1.
Selection of Wire
a.
Wiring: For extended scanner wiring up to 500 feet, and for shorter lengths to reduce signal
loss, use a shielded wire (Belden 8254-RG62 coaxial cable, or equal) for
each scanner wire
of UV1, UV2 and
each red wire
of the 45UV5. The ends of the shielding must be taped and
not grounded.
b.
Asbestos insulated wire should be avoided.
c.
Multiconductor cable is not recommended without prior factory approval.
2.
High voltage ignition wiring should not be installed in the same conduit with flame detector
wires.
3.
INSTALLATION—INFRARED SCANNER TYPE 48PT2
Where possible, obtain the burner manufacturer’s instructions for mounting the scanner, otherwise
proceed as follows:
A single scanner is used to detect both pilot and main flames. The sight pipe on which the scanner
mounts must be aimed so that the scanner sights a point at the intersection of main and pilot flames.
Proper scanner positioning must assure the following:
1.
Reliable pilot flame signal.
2.
Reliable main flame signal.
3.
A pilot flame too short or in the wrong position to ignite the main flame reliably, must not be
detected.
4.
Scanner must have an unobstructed view of flame being monitored.
5.
Flame being monitored must completely cover the scanner field of view.
6.
To avoid nuisance shutdowns, it is important to avoid sighting hot refractory and to keep scan-
ner temperature low (below 125° F) (52°C).
7.
When the proper position has been established, drill a hole through the furnace wall and install a
4" to 8” length of threaded
l
/
2
” black iron pipe on which to mount the 48PT2 scanner.
8.
When satisfactory sighting position has been confirmed by operating tests, the sight tube should
be firmly welded in place.
CENTER LINE
OF MAIN FLAME
SCANNER
LINE-OF-SIGHT
SCANNER TARGET
ABOVE REFRACTORY
COMBUSTION
CHAMBER
PILOT
BURNER
SCANNER
SCANNER
SIGHTING TUBE
MAIN
BURNER
SCANNER MUST NOT
SIGHT REFRACTORY
