User Guide

TRACKING ADJUSTMENT TO CHART TIME LINE
To adjust the pen arm arc length to accurately track the chart time line, gently slacken the two pen arm clamp screws
shown in Fig. 4 and increase or decrease the pen length by sliding the metal pen arm in or out until the pen records along
the chart time line across the whole of the chart scale length. Re-tighten the two clamp screws. Note the red pen only must
track the chart time line, other pens fitted must be set to clear each and one another.
CHART DRIVES
The chart paper, mounted on a clamping hub, is driven by a chart drive mechanism.
Depending on requirement the chart drive will be a mechanical spring wound , battery operated or electrically powered
mechanism.
Mechanical spring wound versions employ a chart paper clamp and winder hub which must be sufficiently wound by
hand but must not be over-wound.
Electric synchronous motor versions must be powered by mains supply and connections are made to a terminal block
mounted inside the recorder beneath the chart plate.
Access to the terminal block is gained by removing the chart plate, and mains supply cable is to be fitted through the cable
gland provided in the lower case wall.
It is important to properly select and connect the supply voltage. The live line should be switched and fused with a 2 Amp
fuse. The supply should be earthed and connected to the appropriate terminal within the recorder.
The chart drive hub employs a lever clamp which must be pressed firm enough to ensure the two locating pips pierce the
chart paper.
Battery Operated versions are powered by a single AA (LR6) alkaline battery fitted into a compartment mounted onto the
chart plate.
To fit a battery, first open the compartment by turning the cap counter-clockwise using a flat blade or coin. Insert the
battery so the positive terminal is uppermost.
Replace the cap, and lock by turning the cap clockwise with a flat blade or coin to its stop.
The chart drive hub is a sliding clamp type which must be pressed slightly firm to clamp the chart paper.
To remove the chart plate entirely from instruments fitted with battery operated chart drives, a separable connector is fitted
to the leads between the battery compartment and the chart drive itself.
To disconnect, pull apart the connector housings only, do not pull the wires or damage will occur. To replace, plug the
housings together and push until fitted correctly, the housings can be fitted one way only.
LINKAGE AND PIVOT ATTACHMENTS
The instrument employs similar linkage attachment whether the measuring system is temperature, pressure or differential
pressure.
The diagram and glossary below is provided to supplement the figures presented throughout this manual to show the
terminology and correct arrangement to ensure friction free linkage movement and therefore accurate pen traces.
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For instruments fitted with mains supply chart drive motor, the mains must be switched
off before making any mechanical adjustments or carrying out any
maintenance or fault finding procedures.