5322A-LOAD
Instructions
4
Use the Load for Leakage Current
Tests
Select the load resistor based on the appropriate
voltage amplitude for the test or the value
recommended in the hipot tester’s calibration
procedure. A load resistor is connected to the Output
terminals when a resistor's red and black terminals
are shorted together using a high-voltage shrouded
banana jumper lead.
See
Paralleling Resistors
for making additional
resistance values. See the
5322A Operators Manual
for more detailed application information.
W
Caution
To avoid damage, never exceed the
maximum rated voltage, power, and
current limit of the Product.
Usage Limits for Safe Operation for Each
Load Resistor
Safe operation of the Product depends on the amount
of voltage and the length of time it is applied to the
Product. For the 10 k
Ω
, 35 k
Ω
, 50 k
Ω
, 100 k
Ω
, and
250 k
Ω
resistors, there are time limits where the
higher-voltage levels can be safely applied. This is
graphically shown in Figure 4 for the 10k, 25k, 50k,
100k, and 250k resistors.The maximum voltages can
be applied for up to 3 minutes for these resistors. Due
to self heating, exceeding the 3-minute limit for high
voltages can cause both degradation of performance
and a permanent shift in the resistor value. However,
reduced-voltage levels can be safely applied for
increasing longer times. At specific levels, sustained
voltages can be applied indefinitely. The other
resistors (500k, 1M, 5M and 10M) do not have a time
limit for the maximum voltage (5500V). See Figure 4.
Safe Area
0
1000
2000
3000
4000
5000
6000
1
10
100
Time (min)
V
o
lt
ag
e (
V
)
250 k
100 k
35k/50k
10k
ehq101.eps
Figure 4. Safe Area Chart
Example
The 100 k
Ω
resistor can withstand 5500 V for
3 minutes while it can withstand 4000 V for
60 minutes or longer.
Paralleling Resistors
The Product can output additional values by placing
combinations of the nine resistors in parallel as shown
in Table 2.
To place resistors in parallel, short together
combinations of the given resistors’ red and black
terminals using the supplied high-voltage shrouded
banana jumper leads. For example, to parallel the
10 k
Ω
and 25 k
Ω
resistors, short the 10 k
Ω
red and
black terminals, and the 25 k
Ω
red and black
terminals. This places these two resistors in parallel at
the Product Output terminals. The resultant output is
7.14 k
Ω
, for a 70 mA leakage current at 500 V, as
shown in Table 2.
In Figure 5, the 10k Ohm, 25k Ohm, and 50k Ohm
resistors are in parallel, giving an output of 6.25 k
Ω
.
HiPot
Tester
Ieu003.eps
Figure 5. Leakage Current Test Connection
The maximum applicable working voltage for parallel
combinations is the maximum voltage of the resistor
with the lowest voltage rating.
W
Caution
Do not exceed the specified
voltage limits of any given
resistor.
