External Standard Pt100
1
2
3
7.2 Power
ON
•
To power the instrument press the back panel switch -
ON
-
The indication of the following running figure will appear for few seconds while a diagnostic routine checks critical
circuits and components.
CL551
•
Once the diagnostic routine is ended , the heater is forced to continuous cooling by means of a ventilation fan at its
maximum speed. A green Led is lit on until the set-point is confirmed or a new set-point value is entered.
The display shows the current heater temperature and the last set-point value entered.
SP : 150.0
T : 23.5 °C
•
In the example above, the display shows a blinking message (
SP:150.0
) until the operator validates the value of
150.0
as the relevant set-point by pressing the
<E>
key.
•
Using the <
▲
> / <
▼
> keys a new set-point value can be selected to become the relevant set-point value, when the
operator validates it by pressing the
<E>
key. An acoustic beep, together with a temporary indication (
■
) right on the
screen, will indicate that the value has correctly been stored into memory.
7.2.1 Display
resolution
CL551
provides two resolutions of the display: 0.1 °C and 0.01 °C.
To select the correct resolution press several times the
<F>
key until you obtain the following display:
T : 23.5 °C
Res.: 0.1
•
Press
<
▲
>
key to have 0.01°C resolution.
T : 23.56 °C
Res.: 0.01
•
Press the <
F
> key to return to normal operative conditions. The indication will return to the following indication:
T : 23.56 °C
SP: 150.0
Note :
If no further indication is supplied by the operator, the instrument automatically resumes the initial conditions.
7.2.2 Temperature
switch
test
CL551
has been designed for the set-point control of temperature switch. For this purpose, two terminals for the
electrical connection to the thermostat under test are installed on the rear part of the instrument, while on the front side of
it, a red LED indicates:
−
close contact
<ON>
(light on)
−
open contact
<OFF>
(light off)
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