Spirax Sarco LP30, Инструкция по установке и обслуживанию

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IM-P402-44 AB Issue 15 10
3.3 Cutting the probe tip
The probe is normally installed vertically, but for probe tip lengths of up to 500 mm (20") it may
be inclined by up to 45 ° from the vertical. The low alarm switching level is at the extreme end
of the probe tip, which is cut to length to give the required alarm level.
LP30 probe tips are retained by a thread, pin and lock-nut:
-
Earlier probes were retained by two pins only.
- A compatable tip is available to special order.
For existing installations, it is important to check which type of connection is used before
cutting the probe tip to length.
3.3.1 Procedure for cutting the tip:
- Screw the lock-nut onto the probe fully, but do not tighten it at this stage.
- Use an M6 spanner on the flats of the probe tip connector to prevent it rotating.
WARNING: If the threaded end of the connector is allowed to rotate in the probe body,
the internal wiring will be damaged.
- Screw the probe tip onto the probe until the hole in the probe lines up with the bottom of
the slot in the probe tip (see Figure 5).
- Support the assembly and tap in the retaining pin until an equal length protrudes from
each side of the probe tip.
- Tighten the lock-nut onto the probe tip (5-7 N m, 4-5 lbf ft).
-
Ensure the boiler water is at the required low alarm level.
- Mark a line down the length of the probe tip using a water-soluble felt pen.
- Temporarily fit the probe and tip to the boiler ( ½ " BSP taper for standard LP30 and ½ " NPT
for UL/FM versions), hand tight, without using PTFE tape.
- Remove the probe and note the point at which the ink is dissolved by the water.
-
Use a fine hacksaw to cut the probe tip to this length (see Figure 6).
- De-burr tip.
- Carry out the probe clearance test procedure (see Section 5, 'Probe clearance test
procedure') and record the results.
Note: A chart is provided for recording this data.