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PULSE Installation, Commissioning and Servicing Manual - Revision 19
6.2 Lobe Meter (Ultra Diesel)
Due to the Lobe Meter having no mechanical adjustment in its design, the Ultra encoder
incorporates a calibration facility which can compensate volume errors within a ±2%
range, with a resolution of approximately ±0.1%.
The encoder uses a “Hall Effect” device to detect the rotation of a magnet which is
mounted at the end of a shaft within the meter body. The magnetic field is coupled to
the Hall Effect device through an aluminium cover plate, which avoids the necessity for an
extended shaft and seal.
Encoder
Cover
Figure 17� Lobe Meter
6.3 Calibration Procedure
When a test delivery is outside of allowable limits, the following steps must be performed
to calibrate the Lobe Meter:
1. To gain access to the encoder PCB assembly, remove the encoder cover by undoing
the three M4 nuts holding it in place.
ON
1
2
3
4
LED
Calibration
Switch
SW1
DIP Switch
SW2
Figure 18� Encoder PCB
