Honeywell Searchline Excel Cross-Duct Technical Handbook page 33

MAN0889_Issue 3_03/13 Searchline Excel Cross-Duct Technical Handbook
3. Installation and Operation
Supply Voltage
Check that the supply voltage applied to the unit is within the specified 18V to 32V range (Transmitter and
Receiver) or 18 to 28V range (Heated Reflector Panel) and is stable. Enter the supply voltage and stability,
e.g.
22.5V, stable,
19V, +2V fluctuation
Earthing
Inspect the earth connections to the units. If the unit is connected to local metalwork or the safety/general
use earth, enter 'Local Safety. If the unit has been isolated from local metalwork/ earths and is connected to
a clean, instrument earth, enter Instrument earth. (See section 3.3, Electrical Connections).
RFI/EMC
Assess the installation, cabling and its close surrounds for known/potential sources of excessive RF/
Electromagnetic Interference. Such sources could include radio/radar transmission antennae, high voltage
switch-gear, large electrical generators/motors etc.
Searchline Excel Cross-Duct complies with the most stringent requirements specified in EN50270. It is therefore
more likely that the field cabling will pick up interference directly on the 4 - 20mA and 0V connections and that
this will affect the reading received at the control room.
Enter brief details of known/potential EMI sources that are within five metres of the gas detector and/or its
cabling. If cable is unscreened or inadequately protected, note concerns.
Examples of the sort of information to enter are:
10m cable, unscreened, Radar, 2m from Receiver,
Cable routed over 400kW generator
(See section 3.3 Electrical Connections).
Contaminants
Assess the installation and its surrounds for sources of contaminants that could build up on the unit's windows.
Such contaminants could include oil mist, heavy sea spray, drilling mud, dirty exhaust fumes, wave splash
etc.
If there is a realistic possibility that such contaminants could cause a significant problem, enter a brief
description, e.g.
Drilling mud spray,
Diesel generator exhaust
Test Filter
After completing the installation procedure, enter the DISPLAY mode and test the gas detector response with
a plastic test filter. Enter the nominal value of the test filter, and the unit's displayed response. When testing
in future, use the same test filter and compare the response to the value obtained at installation. See Chapter
4, Maintenance.
4 - 20mA Loop Integrity
Test the 4 - 20mA loop integrity by forcing the unit to output a known current and monitoring this at the control
room or with a multimeter inserted into the loop. Mark the appropriate box.
33