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Rockwell Automation 1769-OV32T Compact Module User Manual

Page 19

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Compact 32-point Solid-state 24V dc Sink Output Module 19

Publication 1769-IN073B-EN-P - September 2005

Transistor Output Transient Pulses

The maximum duration of the transient pulse occurs when minimum load is connected to the
output. However, for most applications, the energy of the transient pulse is not sufficient to
energize the load.

The graph below illustrates that the duration of the transient is proportional to the load
current. Therefore, as the on-state load current increases, the transient pulse decreases.
Power-up transients do not exceed the time duration shown below, for the amount of loading
indicated, at 60°C (140°F).

ATTENTION

A transient pulse occurs in transistor outputs when the external DC
supply voltage is applied to the output common terminals (e.g. via the
master control relay). The sudden application of voltage creates this
transient pulse. This condition is inherent in transistor outputs and is
common to solid state devices. A transient pulse can occur regardless of
the controller having power or not. Refer to your controller’s user
manual to reduce inadvertent operation.

0.4

1.0

0.9

0.8

0.7

0.6

0.5

0.3

0.2

0.1

0.0

1000

900

800

700

600

500

400

300

200

100

1

30519-M

On-State Load Current (mA)

Transient Pluse Duration as a Function of Load Current

Time-Duration of transient (mS)