GRAPHTEC midi LOGGER GLT400 Quick Manual Start page 11

The analog input section of the GLT400 contains a capacitor to improve the noise removal
capability.
Therefore, when the input terminal is in open sate, the measurement result may be affected by
the signals of other channels. In such a case, set the input to "Off" or short between +/-
terminals. When the signal is input properly, there is no influence from other channels.
If the measurement value fluctuates due to external noise, we recommend the following
countermeasures. (The effect depends on the noise type.)
Ex 1: Connect the GLT400's GND to ground.
Device to be
measured
Z
3
Ex 2: Connect the GLT400's GND to the GND of the device to be measured.
Ex 3: In the AMP setting menu, set the filter to any setting other than "OFF" .
Ex 4: Set the sampling interval which enables GLT400's digital filter (see Table below).
Number of Measuring
Channels
*1
1 channel
2 channels or less
5 channels or less
10 channels or less
11 to 20 channels
21 to 50 channels
51 to 100 channels
101 to 200 channels
*1 Number of Measuring Channels is the number of channels in which input settings are NOT set
to "OFF" .
*2 Temperature cannot be measured when the sampling interval is set to 10 ms/20 ms or
50 ms.
The commercial power frequency to be used must be set. Set the AC power frequency to be used.
Select items
Unused channels
Noise countermeasures
Thermocouple
Allowed Sampling
Interval
10 msec or slower
20 msec or slower
50 msec or slower
100 msec or slower
200 msec or slower
500 msec or slower
1 sec or slower
2 sec or slower
50 Hz
60 Hz
R1
Input terminals
R2
Sampling Interval which
enables Digital Filter
*2
*2
*2
Description
Area where the power frequency is 50 Hz
Area where the power frequency is 60 Hz
10
GLT400
+
Vin
-
Z Z
1 2
50 msec or slower
125 msec or slower
250 msec or slower
500 msec or slower
1 sec or slower
2 sec or slower
5 sec or slower
10 sec or slower