Trouble-shooting
13. TROUBLE-SHOOTING
Data acquisition system ALMEMO 5690-2M can be configured and pro-
grammed in many versatile ways. It is suitable for connecting a wide variety of
very different sensors, additional measuring instruments, alarm signaling de-
vices, and peripheral equipment. Given these numerous possibilities the de-
vice may in certain circumstances not behave quite as expected. The cause of
such unexpected behavior is only very rarely a device defect; more usually it is
incorrect operation by the user, an invalid setting, or unsuitable cabling. In
such event try to pinpoint and clear the problem with the aid of the following
tests.
Error
No display, display malfunction, keys do not react
Remedy
Check the power supply, charge the battery, switch off and then on
again.
If necessary, re-initialize; (see 7.5).
Error
Measured values are incorrect.
Remedy
Check all the channel programming very carefully, especially the
base value and zero-point (sensor programming and special functions).
Error
Fluctuating measured values or the system hangs in mid-operation.
Remedy
Check the cabling for any inadmissible electrical connections.
Unplug any suspicious sensors.
Connect hand-held sensors in air or phantoms (for thermocouples short-
circuit AB, for PT100 sensors use 100
W
) and check.
Connect the sensors again one at a time and check successively.
If a fault persists for any one connection, then check all wiring; if neces-
sary, insulate the sensor and eliminate interference by using shielded or
twisted wiring.
Error
Data transmission via the interface does not function.
Remedy
Check interface module, connections, and settings.
Are both devices set to the same baud rate and transmission mode ? (see
12.5.3)
Is the correct COM interface on the computer being addressed ?
Is a printer in the ONLINE status ?
Are the handshake lines DTR and DSR active ?
To check the data flow and the handshake lines a small interface tester
with LEDs comes in very handy; (in ready-to-operate status the data lines
TXD, RXD carry negative potential of approx. -9V and the LEDs light up
green, whereas the handshake lines DSR, DTR, RTS, CTS carry approx.
+9V positive voltage and the LEDs light up red; for the duration of data
transmission the data LEDs must flash red).
Test data transmission by means of a terminal (AMR-Control, WIN-Con-
trol, WINDOWS-Terminal).
Select output channel interface U using command ´
A1
´,
Address the device using its assigned device number´
Gxy
´ (see Manual
6.2.1).
Enter <Strg Q> for XON, if the device is in the XOFF status.
ALMEMO
®
5690-2M
83