ROC800-Series Instruction Manual
Revised July-2017
Input/Output Modules
4-15
Virtual DO
ROCLINK 800 provides a “virtual DO” software setting to support
fieldbus devices, which may require the toggle characteristics of DO.
For further information, see the
ROCLINK 800 Configuration
Software User Manual (for ROC800-Series)
(part D301250X012) or
the
ROCLINK 800 Configuration Software User Manual (for
ROC800L)
(part D301246X012).
4.8
Discrete Output Relay (DOR) Modules
The five-channel DO Relay (DOR) module provides LEDs that light
when each output is active. DOR modules use dual-state latching relays
to provide a set of normally open, dry contacts capable of switching 2 A
at 32 Volts dc across the complete operating temperature. Using
ROCLINK 800, you can configure the module as latched, toggled,
momentary, or Timed Duration Outputs (TDO). The DOR can either
retain the last value on reset or use a user-specified fail-safe value.
Note
:
Since the DOR latches, a power failure does not change the
relay’s state. The relay retains the state (open or closed) it had
upon failure.
Figure 4-14
displays the field wiring connections to the output circuit of
the DOR module.
Caution
The Discrete Output module is designed as a “dry” relay contact.
Applied voltages in excess of 32 Vdc or any AC voltage may damage the
module.
When a request is made to change the state of a DOR, the request is
immediately sent to the DOR module. There is no scan time associated
with a DOR. Under normal operating conditions, the DOR channel
registers the change within 12 milliseconds. If the DOR is in momentary
or toggle mode, DOR channels register the change within 48
milliseconds.
The DOR modules draw power for the active circuitry from the
backplane.
Note
:
On power up or reset, the DO Relay module’s LEDs enter
indeterminate state for a few seconds as the module self-
identifies. The LEDs may flash, stay on, or stay off for a few
seconds.