User Guide

Description of Operation
Temperature recorder (see Fig. 5.)
As the temperature rises, the fluid in the thermometer bulb expands and partially uncoils the spiral Bourdon tube
fitted inside the instrument. This movement is transferred by a mechanical linkage to the pen arm which records
the temperature on a calibrated chart.
Pressure recorder
On medium and high pressure ranges an increase in pressure partially uncoils a Bourdon tube fitted inside the
instrument. This movement is transferred by a mechanical linkage to the pen arm which records the pressure on a
calibrated chart.
A capsule stack or diaphragm system is fitted for low pressure ranges and the expansion of the system resulting
from an increase in pressure is transferred by a mechanical linkage to the pen arm.
8
Fig. 5
Bourdon tube
Set-up spring
Linearity adjustment
Ratio arm pivot
Control unit
Drive link
striker pin
Coarse zero adjustment
Compensator
Setting pointers
Control arm
Terminal block
Relays
Control unit
fixing screws
Setting pointer
clamp