XS series operating manual 
 
XS user manual v0.55  - 26 - 
The measurement range is defined by the following formula: 
 
(Utest / Umax generator) x 20 G  
 
This gives the following board for the 500, 750, 1000 et 1500V standard voltages  
 
 
Measurement accuracy  
 
2000 digits numeric display with unity indication (K, M, G, T). 
Accuracy (% of the reading, 1U = 1 digit) : ±(1% + 1U) 
 
NORMAL mode : from 1.00MΩ to 20GΩ  
Input impedance = 10kΩ ± 1%. 
 
CAPACITANCE  mode:  from  1.00M  to  20G  with  an  accuracy  equal  to  the  NORMAL  mode 
accuracy ±100k 
Input impedance = 10 M ±1% 
Measurement threshold  
 
The megohmmeter function can operate either with one or two measurement threshold(s) between 
1M up to 20G. 
A measurement is PASS after comparison between the displayed value and the thresholds. 
When looking for a value only higher than a limit, the LOW THRESHOLD is used to set the limit and 
the HIGH THRESHOLD is not used by setting a value equal to the maximum resistance (basically 
20G). 
When looking for an insulation resistance higher than a limit but not too much high ( which can 
means that the specimen is not correctly connected), then the LOW THRESHOLD is set the 
minimum insulation value expected and the HIGH THRESHOLD is set to the maximum insulation 
value expected. 
 
Setting examples: 
 
PASS  ( insulation > LOW limit ) 
FAIL ( insulation < LOW limit) 
PASS ( insulation > LOW limit + < HIGH limit) 
FAIL (insulation > HIGH limit ) 
 
* threshold not active