Data Sheet

B
Application notes
Intervention Modules
The demand for security apparatus, heating, air conditioning or
efficient energy use in offices, hotels, and private homes or in
industrial space is growing constantly, leading to the installation of
increasingly complex electronic systems. But what happens if these
systems malfunction and a qualified service technician will only be
available in a few hours, or even days?
With the use of carefully installed intervention modules, a trained
caretaker or security guard can be in a position to recognize
interruptions in service, and by manual intervention perform the
necessary override actions to maintain system operation until a repair
can be effected.
Digital Override control module
Auto-Off-On output module (Type 19.21)
Many processes or systems are automatically controlled by an
electronic control system or by a Programmable Logic Controller.
In the event of an electronic system malfunction it is important,
in order to avoid damage or downtime, to plan for the possibility
of controlling the process manually. An Auto-Off-On Module can
provide this, located between the output of the electronic system
(Controller) and the process to be controlled (End Process) - bypassing
the malfunctioning control unit in a planned way. For malfunctioning
electronic systems, the process to be controlled can be manually
switched On or Off, as needed, using the switch on the front of the
unit. Under healthy functioning of the electronic system, the switch is
left in the Auto position. In this configuration the process is controlled
by the normal functioning of the electronic system and its output. It
may be important to know (remotely) if the process is being controlled
manually or automatically, in which case the feedback contact on the
Auto–Off–On module 19.21 can provide this.
Analogue Override control module
Analogue output module (0…10)V (Type 19.50)
This module can be installed where there is need to give a manually
adjustable analog signal (0…10)V priority over an analog signal
from a electronic control unit or PLC, or to override and replace a
malfunctioning signal.
The Analogue override module provides, by the selection switch on the
front panel, a (0…10)V output signal either generated automatically
or by hand. With the selector switch in position “A“ (Automatic)
the (0…10)V signal at Yout-A2 is derived from the controller signal
applied to terminals Yin-A2. In position “H” (Hand) the controller
signal is ignored and the (0…10)V signal is derived directly from the
potentiometer setting on the module front panel.
Operation in switch position H is indicated by a blinking yellow LED,
and by the opening of contact 51-52 – which could be used to report
the override condition to the central control room.
The level of the (0…10)V output signal is displayed by 3 green LEDs,
set at >25%, >50% and >75%
Please see general technical information
X-2017, www.findernet.com
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SERIES
19 SERIES
Relay actuators & Status indicating modules