Table of Contents
Advertisement
Installation & Operation Manual
BMS MODBUS
Connections for Master/Slave protocols used in Building Management Systems to communicate between
devices including the GDPX+ panel are used with [BMS MODBUS] – RTU.
For MODBUS communications, a shielded and twisted cable is used.
Any cable with similar characteristics can be used to connect all the devices together.
The shielding can be of 2 types: braided [mesh of thin conducting wires] or foil (consisting of a thin sheet
of metal covering the twisted wires). If you are encountering noise or irregular problems with a modbus
link, the problem is likely related to grounding, incorrect shielding or wiring mains power next to Modbus
wiring.
Communication issues may occur where the bus length is too long or high baud rates are used.
In this instance – the [BMS Modbus Termination Switch] on the board may help the quality of the data
signal when turned on at the last and/or first device!
SOUNDER-STROBE
There are connections for an external sounder alarm/ strobe lighting to activate on alarm.
24V DC OUTPUT
This is a permanent 24V DC power output for external auxiliary devices. Max output: 200mA
INPUT 1 & INPUT 2
These terminals are connections for selectable external devices which send an 'open/close' circuit signal
to the GDP-X panel such as a current monitor, CO2 monitor or extra emergency shut buttons and heat
sensors - selectable in the Settings menu.
FIRE PANEL
The terminal for fire alarms is detailed on the circuit board as [FIRE PANEL].
HEAT SENSOR
The terminal for heat sensors/ thermal links is detailed as [HEAT SENSOR]. Additional Heat Sensors can
be connected to [INPUT 1] or [INPUT 2] terminals.
EM STOP
Connections for remote emergency shut-off or stop buttons is detailed on the circuit board as [EM STOP].
Additional shut-off buttons can be connected to [INPUT 1] or [INPUT 2] terminals.
GDPXPLUS - IOM Iss: 8 02-21
Merlin GDPX+
7
Advertisement
Table of Contents
