PISA11.CLASS2

PISA11-Series

Large input capacitors of drives, monitors or other similar loads can result in an unintended shutdown of the module

when trying to turn-on such loads. This especially can occur after a reset or by turning on a load via the push button or

the external signal input. The PISA protection module is designed to be exceptionally compatible with such types of

loads. The module can turn-on as much capacitance as possible and comprises several different protection mechanisms

to protect against an unintended shutdown or damage of the unit.

The permissible capacitor sizes which can be connected to the output of the PISA module depends on the load current

itself as well as on the characteristic of the load.

The following tables show two typical cases (case A and case B) for the permissible capacitors, which can be connected

on the outputs without shutdown of the protection module. The listed values are valid for the entire temperature

range.

Case A: All outputs are loaded.

The minimum values are worst-case figures for the permissible capacitors which are defined with an additional

constant current load and with the maximum permissible total current of the PISA protection module. See also the

parameter list below the table.

The typical values are defined with an additional resistive load. See also the parameter list below the table.

Permissible Capacitors

PISA11.CLASS2

Per channel

58mF

14mF

All four outputs together

typ.

58mF

min.

14mF

Parameters: Typical values are with an additional 1.9A resistive load per output.

Minimum values are with an additional 3.7A constant current load per output.

Case B: Only one output is loaded

The minimum values for the permissible capacitors are defined with an additional constant current load according to

the parameter list below. During the tests, only one output is loaded and all others are not.

The typical values for the permissible capacitors are defined with an additional resistive load according to the

parameter list below. During the tests, only one output is loaded and all others are not.

Permissible Capacitors

PISA11.CLASS2

Per channel

typ.

68mF

min.

45mF

Parameters: Typical values are with an additional 1.9A resistive load. Minimum values are with an additional 3.7A constant current

load.

Fig. 7-1 Test setup for capacitive load measurements

Power

Supply

-

+

PISA11

Protection

Module

Out-1

+

-

-

Out-2

Out-3

Out-4

Distribution Node

10mOhm

R / I

Load

R / I

Load

R / I

Load

R / I

Load

*) The allowable capacitor size can

be larger with power supplies equal

or smaller 20A output current

May 2014 / Rev. 1.7 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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