User Guide

DigiTemp Digital Thermometer - Intrinsically Safe Version

Instruction Manual

Page 2

Variants

The DigiTemp is available in several variants using either a thermocouple or a platinum RTD probe, and offering several tempera-

ture ranges. In addition, the instrument is available with display units of degrees Celsius or degrees Fahrenheit.

Cleaning

To remove the risk of discharges due to static electricity, cleaning should only be undertaken using a damp cloth. Strong solvents

should not be used to clean the window.

Battery replacement

When the battery is nearing the end of its life the 'LOW BATTERY' warning light above the display will begin to flash. At this point

the battery has less than six months' life remaining and is due for replacement.

WARNING: For continued protection it is essential that only a battery pack of the same type is fitted. Battery replacement

must only be undertaken with the DigiTemp removed from the hazardous area.

Tools : The following tools will be required to change the battery -

Flat-bladed screwdriver approx. 6mm wide,

Cross-head screwdriver Pozidrive No. 1,

Nut-spinner or spanner 10mm A/F,

Soldering iron and solder,

Link wire approx. 50mm.

Procedure : (See Figure 2.)

1. Remove the bezel by unscrewing it from the case, anticlockwise. The window and its sealing ring may come off with the

bezel but must in any case be removed.

2. Unscrew the two screws securing the dial (at the 9 o'clock and 3 o'clock positions) and remove the dial.

3. Bypass the fuse, which is to be found immediately to the left of the display, by soldering the link wire across its two

leads. The circuit board pads which the fuse is soldered to are marked 'FUSE' and are enclosed in a small rectangle.

This is an important precaution whilst changing the battery. The fuse is very sensitive and an accidental touch of the cir

cuitry against something metallic can result in the fuse rupturing; it must then be renewed.

4. Unscrew the two screws securing the circuit board assembly (at the 11 o'clock and 5 o'clock positions). Notice a short

bonding strap between the 5 o'clock circuit fixing screw and the dial fixing pillar at the 3 o'clock position; this must be re-

fitted as found during re-assembly. Lift the circuit assembly out of the case.

5. Remove the two nuts holding the retaining plate across the battery pack. Remove the plate and the battery pack from

the case.

6. The red lead from the battery is soldered to a pad on the circuit board (marked '+'). The black lead is either soldered to a

switch, or if this is not fitted, then to a pad on the circuit board (marked '-'). Unsolder the battery leads at the appropriate

points.

7. Replace the battery by soldering the leads of the new pack to the appropriate points. Take care to make a neat joint with

a minimum of bare wire. Trim any surplus wire projecting from the soldered-side of the circuit board.

8. Complete the operation by reversing the actions taken in 1 to 5 above.

Take care not to overtighten any of the fasteners involved.

For safety reasons the temporary link across the fuse must be removed.

When refitting the bezel make sure that the sealing gasket is between the window and the case. Tighten the bezel with

firm hand pressure.