PISA11.CLASS2
PISA11-Series
P
ROTECTION
M
ODULE
24V,
4
O
UTPUTS
Shutdown behavior to avoid under-voltage situations on the supply voltage
A further limitation of the output current activates when the supplying power source can not deliver enough current
to support all loads without bringing the power source into overload followed by a voltage drop. In such an event, the
voltage dependent current limitation of the input stage of the protection module is activated (safeguard circuit). This
safeguard circuit acts like a valve only permitting so much current so that the supply voltage does not fall below 21V.
The period of time for how long the protection circuit is able to actively limit the current depends on the difference
between input and output voltage and the current which flows through the PISA protection module and is limited to
a maximum of 5s. All four outputs will shutdown simultaneously.
Shutdown times for a short circuit condition across the outputs can be found in Fig. 6-2.
Fig. 6-2
Active current limitation – Period of time in current limiting mode until the outputs will shutdown
Adjustable
Power
Supply
+
-
Load
I= 0,8*I
OUT
Short
I
OUT
PISA
Module
Test Setup
I
OUT
10ms
100ms
1s
10s
2A
4A
6A
8A
10A
12A
14A
16A
18A
20A
45°C
Output Current
(Sum-current of all output channels - I
OUT
)
5s
Shutdown Time, typ.
20°C
Test Procedure:
1. Set the output current of the adjustable power supply to
the test current value.
2. Set load current to 80% of the test current and wait for
a thermally stable condition.
3. Short circuit the output of the PISA module and measure
the time until the outputs shutdown.
No single output channel is allowed to be overloaded
The output current is the sum of all outputs.
Feb. 2012 / Rev. 1.3 DS-PISA11.CLASS2 - data sheet -
All parameters are specified at 24Vdc input, 25°C ambient temperature and a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278-0 Germany
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