VESDA by Xtralis
VESDA VFT-15 Product Guide
www.xtralis.com
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It is the responsibility of the installer to provide a suitable environment to prevent damage to the equipment,
and to reduce external interference to a level within which the equipment can operate as defined by its
specification. The provision of warning, caution and danger information to the end user is within the task of the
installation provider, and not the instrument manufacturer.
The purpose of the guide is to assist the installation provider, but it is not intended to be a full and complete set
of instructions. The installer shall be more qualified to take the relevant technical, safety and legal decisions.
D.4.1
Electrical Supply
The supply voltage and frequency must be maintained within the equipment requirement specification. Any
breaks in supply or reductions in voltage below the specified minimum will result in equipment shutdown.
When this problem exists, an uninterruptible power supply should be used to supply the equipment.
If the electrical supply is known, or suspected, to be subject to noise pulses produced by motors, fluorescent
lamps, storms and lightning, or other causes then mains filtering must be fitted to reduce the peak amplitude
to less than twice the nominal RMS voltage.
The equipment metal case must be connected to an earth. To protect personnel this earth should be free from
voltages greater than 10 V peak.
It is recommended that galvanically isolated power supplies (in accordance with UL1481) are used since the
RS485 inputs/outputs are not usually isolated from the equipment internal zero volt line.
The RS232/RS485 converter should also be galvanically isolated.
