Honeywell XNX-AM Series, Technical Manual

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XNX Universal Transmitter
Safety and Information 7
• Enclosures of remotely mounted sensors contain aluminum. When installed in
Zone 1 locations, be careful to avoid ignition hazards due to impact or friction.
• Install the junction box according to local codes and manufacturer’s requirements.
• The enclosures of remotely mounted 705HT sensors contain aluminum. When
installed in Zone 1 locations, be careful to avoid ignition hazards due to impact or
friction.
• Power off the transmitter before changing S3 or S4. Failure to do this will
permanently damage the transmitter. Both switches must be set in either Source
or Sink prior to applying power.
• Do not set the minimum or maximum controller alarm levels at less than 10% or
greater than 90% of the full scale range of the sensor. CSA and FM agency limits
are 60% LEL or 0.6mg/m
3
.
• When configuring or communicating with the transmitter using the front panel
displays, resume monitoring by exiting all menus and returning to the General
Status menu manually. No time outs are invoked.
• When selecting a new target gas for units with a Searchpoint Optima Plus, the
sensor must be recalibrated.
• XNX Universal Transmitters carrying UL/CSA/FM approvals that are configured for
devices measuring %LEL will not allow adjustments to the full scale value. The
range is fixed at 100%.
• There is a potential loss of sensitivity during exposure to high concentrations
of H2S. Under these conditions, set the control unit to latch at overrange. In
standalone configuration, set alarms to latching. When resetting the overrange or
alarm, verify correct operation of the transmitter.
• Keep the passwords in a secure area to prevent unauthorized access to the
transmitter. If the passwords are lost, resetting the transmitter will require a
service technician.
• When the transmitter is placed in Inhibit Mode, alarms are silenced. This will
prevent an actual gas event from being reported. Inhibit Mode must be limited
to testing and maintenance only. Exit Inhibit Mode after testing or maintenance
activities.
• Honeywell recommends periodic bump tests (every 30 days or in accordance
with customer site procedures) to the sensor to insure proper operation and
compliance with the functional safety rating of the installation.
• Honeywell Analytics recommends bump testing of ClO2, Cl2, HF, and HCl sensors
frequently and in accordance with customer site procedures to ensure proper
operation and compliance with the functional safety rating of the installation.
• As some test gases are hazardous, exhaust the flow housing outlet to a safe area.
• Exposure to desensitizing or contaminating substances or concentrations causing
operation of any alarm may affect sensor sensitivity. Following such events, verify
sensor performance by performing a functional gas test (bump test).
• When servicing or replacing sensors, reduce the risk of ignition in hazardous
atmospheres by declassifying the area or disconnecting the equipment from the
supply circuit before opening the sensor enclosure. Keep the assembly tightly
closed during operation.
• Take appropriate precautions when using toxic, flammable, or pressurized
cylinders.
• XNX transmitter is SIL2 approved and please refer to XNX transmitter safety
manual (1998-0808) for the detail of SIL certificate.
ELECTROSTATIC DISCHARGE
To minimize the risk of electrostatic discharge:
•
Ground the transmitter adequately
•
Install the transmitter in a manner that will prevent accidental electrostatic
discharges, e.g. ensure that objects do not rub against the housing etc.
•
Clean the enclosure with a damp cloth when necessary