Heating Resistance (Ctd4000-375 Or Ctd4000-650); Temperature Sensors; Safety Thermostat (Ctd4000-375 Or Ctd4000-650); Fan - WIKA CTD4000 Betriebsanleitung

4. Design and function
4. Insert the clamp into the fuse container.
EN
5. Press in the fuse container fully.

4.6 Heating resistance (CTD4000-375 or CTD4000-650)

The resistance is made from stainless steel; the max power
is 630 W and it can become very hot.
The use of the calibrator at continuous high
temperatures reduces the service life of the
resistor. Limit the number of hours at which the
resistance is used at maximum temperatures
to the time required by the calibrator in order to
prolong the life of the resistance.
The equalising block has an opening of 26 mm into which
the inserts for almost any temperature probe size can be
inserted. The function of this block is to make the temperature
in the calibration zone uniform.
The bores are dependent on the temperature probes.
For further information, see 6.7 "Testing or calibrating
temperature probes". Through this, any problems, which
might arise if the wrong tolerances are used, will be avoided.

4.7 Temperature sensors

The temperature sensor used for the reading and
thermoregulation is inserted directly into the equalising block
to display the real temperature value.
10
⇒

4.8 Safety thermostat (CTD4000-375 or CTD4000-650)

The calibrator is fitted with a thermal fuse for the highest
temperature, which has a manual reset button. The thermal
fuse switches off the heating system as soon as there is an
error.
If Ht is showing on the display means, that the temperature
has exceeded the upper limit.
If Ht is on the display:
1. Cool the temperature calibrator
⇒
The temperature must fall to at least 60 ... 80 °C
[140 ... 176 °F] under the high set value (standard).
2. Switch off the calibrator then switch on again a few
second later.
The thermostat has been factory set to 660 °C
±10 °C [1,220 °F ±10 °F] with the CTD4000-650
and to 385 °C ±10 °C [725 °F ±10 °F] with the
CTD4000-375.
If the problem persists, disconnect the calibrator from the
voltage supply and rectify the possible fault.

4.9 Fan

A fan is installed in the calibrator. The fan works with two
different speeds: the control system switches on the fan
at minimum speed with increasing temperature, and at
maximum speed for decreasing the temperature. The fan
keeps the case of the calibrator at a low temperature when
the temperature increases and assist the cooling process.
Every hole at the bottom and at the back of
CTD4000 must be kept free in order to let the air
flow properly.
4.10

Inserts

In order to achieve the greatest possible accuracy, the use of
exactly matched inserts is necessary. For this, the diameter
of the test item must be accurately determined. The bore for
the insert is obtained by adding approx. +1 mm [+0.04 in],
depending on the temperature range.
Following use, the inserts should be removed
using the replacement tools and then the insert
and block should be cleaned. This prevents the
sleeves becoming jammed in the heating block.
WIKA operating instructions, model CTD4000