MAN0964-14-EN_XL4_XL4P_UM
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Protection for Inductive Loads
–
Inductive loads can cause reverse currents when they shut off
that can shorten the life of relay contacts. Some protective measures need to be determined
by an engineer. Below you will find recommendations that will work for many applications. If
you have additional questions on protection from inductive load, consult an application
engineer or Horner Technical Support. Details on devices that may protect outputs can be found
in the Spark Quencher Datasheet, MAN0962, which is located on the website.
Output State on Controller Stop
–
When the controller is stopped, the operation of each output
is configurable. The outputs can hold the state they were in before the controller stopped or
they can go to a predetermined state. By default, relay outputs turn off. For more information
on Stop State see the
8.6 Digital Inputs
NOTE: Refer to the datasheet for XL4/XL4 Prime OCS model you are using for details on jumper
settings.
NOTE: The digital inputs on the XL4/XL4 Prime OCS are designed for low voltage DC inputs.
The inputs are designed to support both positive and negative input modes. For most models,
the mode is set by a jumper setting and a configuration parameter in Cscape. The HE-XC1E6
does not require jumpers, and only requires a configuration parameter in Cscape. All the inputs
on the unit must be configured to the same mode.
Figure 8.6
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Positive and Negative Inputs
In positive logic mode a positive voltage applied to the input will turn the input. The internal
design of this mode is basically a resistor from the input to I/O ground. This mode is sometimes
called “sourcing”
.
In negative logic mode, connecting the input to the I/O ground or zero volts will turn the input
on. The internal design of this mode is basically a resistor from the input to the positive I/O
voltage (usually 12V or 24V). This mode is sometimes called “sinking”.
Some of the digital inputs may support high-speed input functional such as counting or
frequency measurement.
I1
0V
001XLE036
12-24VDC
I1
0V
Positive Logic In Negative Logic In
Positive Logic vs. Negative Logic Wiring
The XL SERIES OCS can be wired for Positive Logic inputs or
Negative Logic inputs.