HBM PX401, Руководство по эксплуатации

Страница: 113 / 552

Electrical connections PMX
PMX
A4354-2.2 HBM: public
113
electrically isolated from the PMX housing, but not from
each other
(see Fig. 8.31) .
The control inputs are available at the Digital IN 1 and IN
2 terminals, as well as at the IN 3 to IN 8 terminals. They
are electrically isolated from the PMX housing, but not
from each other
(see Fig. 8.31) .
Important
Output behavior after switch-on:
S
The digital outputs have a high resistance after switch-on
and retain this status, until the state changes to active. The
change to active status is dependent on the firmware and its
set actions.
S
In the active state, the externally connected voltage source
(see + and terminals) is switched through internally with
low resistance, with the aid of an electronic switch (high side
switch).
Note: The electronic switch switches the + pole of the
voltage source.
S
In the active state, the electronic switch has a high
resistance. If a defined state is expected for this situation
(e.g. the electronic input of a control), a (pull‐down)
termination resistor must be used to terminate the high
resistance state.
S
An external reference potential ( IN ), to which the control
input signals relate, must be connected for the control
inputs.
Important
The PX878 I/O card has electrical isolation between the
analog and digital sections and the basic device.