M&C TechGroup ECP20-2 Operator's manual - Manual (Page 18)

18
Gas sampling and gas conditioning technology 3-1.10-ME
16 TROUBLE SHOOTING
The following table aims to point out possible operational problems and offer solutions to such
problems (not applicable during the starting procedure).
Problem/Indication Possible cause Action/Check
ECP20 is not cooling
°C >
ON
°C <
°C >
ON
°C <
red
No mains supply
Ambient temperature
+2°C

T

+5°C
Temperature sensor faulty
Set point at Pot 3 out of
adjustment
Check for mains supply voltage at
terminals L&N, X1/1+2 against
nameplate. If OK, check fuses F1, F2.
Check ambient temperature.
Disconnect white wires from terminals
X5/5+6 and measure sensor resistance:
107,79 +0,4 Ohm at +20°C ambient; if
there is great deviation change the
sensor.
Adjust the desired temperature with the
trimmer Potentiometer P3 (0,1V/°C) and
control the current temperature at
terminals (X7/3) with an extern voltmeter
(see Temperature Setting and Control).
ECP20 cools
continuously
°C >
ON
°C < red
Transistor BUZ11 faulty Check voltage of the Peltier elements at
terminal X5, 1 and 3 respectively 2 and 4
(see circuit diagram):
> 12V DC = transistor faulty;
Fit the new transistor V1 on the basic
circuit board.