HT instruments HT7051 - Manual (Page 32)

HT2055
EN - 31
11 TECHNICAL SPECIFICATIONS
The accuracy is calculated as [% rdg + (number of dgt) * resolution] at reference condition
indicated in § 11.2
Step/Contact voltage measurement
Measured voltage range Resolution Accuracy
0.01  19.99mV 0.01mV
(2.0rdg + 2dgt)
20.0  199.9mV 0.1mV
200  1999mV 1mV
2.00  19.99V 0.01V
20.0  59.9V 0.1V
Calculated voltage range Resolution Accuracy
0.0  199.9V 0.1V
calculated value (*)
200  999V 1V
(*) The calculated value of step/contact voltage is obtained by the relationship: U
S
=U mis ·
I flt /I gen ;
U
C
=U mis ·
I flt /I gen ;
Fault current range (selectable): 10A  200kA
Input resistance (selectable): 1k , 1M
Noise reducing: DSP 55Hz filtering, 64dB rejection of 50/60Hz noise
Generated current range Resolution Accuracy
0.00  9.99A 0.01A (3.0rdg + 5dgt)
10.0  99.9A 0.1A (3.0rdg + 3dgt)
Generated current: 55A max
Test voltage: <55V
Test frequency: 55Hz
Earth resistance measurement
Measurement range Resolution Accuracy
0.001   1.999 0.001
(2.0rdg + 5dgt) 2.00   19.99 0.01
20.0   99.9
0.1 
100.0   199.9 (5.0rdg)
Open voltage: < 50V AC
Test current: < 7.5A
Frequency of test signal: 55Hz
Influence of probe resistance:  ±(10%rdg + 10dgt)
(Rc, Rp) max (10  + 100R) or 2k considering lower value
Automatic test of probe resistance: Yes
Automatic detection of voltage noise
Ground resistivity measurement
Measurement range Resolution Accuracy
0.00 m  9.99m 0.01m
Calculated value, considering
accuracy of resistance to earth
function
10.0 m  99.9m 0.1m
100 m  999m 1m
1.00k m  9.99km 0.01km
10.0k m  99.9km 0.1km
Principle of measure: Wenner method   = 2** distance* R