MARTINDALE ET4000 Instruction Manual page 51

Martindale ET4000 / ET4500
Step 2: Measuring the voltage drop
Set sub-function to

Select test parameters (Fuse type must be selected).

Connect the test leads to the instrument.

Connect the test leads to the point in the wiring or socket to be tested (see Step

2 of Figure 5.33).
Press the TEST key to perform the measurement.

Store the result, if required, by pressing the MEM key (ET4500 only).

Step 1 - Zref
Figure 5.33: Examples of voltage drop measurement result
Displayed results:
ΔU ........... voltage drop
Isc ........... prospective short-circuit current
Z .............. line impedance at measured point
Zref ......... reference impedance
Voltage drop is calculated as follows:
where:
ΔU ........ calculated voltage drop
Z .......... impedance at test point
Z ...... impedance at reference point
REF
I .......... rated current of selected fuse
N
U ........ nominal voltage (see table below)
N
Testing considerations
If the reference impedance is not set the value of Z

The Z is cleared (set to 0.00 Ω) by pressing the NULL key while the instrument

REF
is not connected to a voltage source.
ΔU using UP / DOWN keys.
( Z
 
U %
 
U Input voltage range (L-N or L1-L2)
n
(93 V  U
110 V
230 V (185 V  U
(321 V  U
400 V
Step 2 - Voltage drop
Z ) I
 
REF N
100

U
N
 134 V)
L-N
 266 V)
L-N
 485 V)
L-L
REF
51
Measurements
is considered as 0.00 Ω.