Horner APG XLt OCS User Manual
Page 35
MAN0878-04-EN CH. 9
August 12, 2009
Page 35 of 100
ECN # 979
9.4
Solid-State Digital Outputs
Solid-state digital outputs are generally used to activate lamps, low voltage solenoids, relays and other
low voltage and low current devices.
Note: The digital outputs used on the XLe/XLt are “sourcing” outputs. This means the output
applies a positive voltage to the output pin when turned ON. When turned off, the output applies
approximately zero volts with respect to the I/O ground.
Figure 9-3 – Typical Output Wiring
The digital outputs used in the XLe/XLt have electronic short circuit protection and current limiting. While
these electronic protections work in most applications, some application may require external fusing on
these outputs.
The digital outputs in the XLe/XLt are typically controlled via %Q bits in the register mapping. Some of
the outputs are designed for high-speed applications and can be used for PWM or frequency output
applications. Please see the data sheet and the chapter on High Speed I/O for additional information.
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 digital
outputs turn off. For more information on stop state see configuration (Chapter 14) for Cscape settings.
The digital outputs feature an output fault bit. %I32 will turn on if any of the outputs experience a short
circuit, over-current or the output driver overheats.
9.5
Relay Outputs
Relay outputs are designed to switch loads that typically have high voltage or current requirements or
require isolation that relays provide.
Note: The design of the XLe/XLt does not require external coil power for the relays to function.
The relays will activate anytime the XLe/XLt is powered.
There are several factors that should be considered when using relays.
Q14
Q15
V+
0V
LOAD
LOAD
10 - 30VDC
Q16
LOAD
J2
J4