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USER MANUAL
66-2071-02
U2 Combination Viewing Head and
Signal Processors
INTRODUCTION
The Honeywell U2 flame monitoring system combines sensing
and processing in one package. The U2 is available in several
models to provide different options. Each model includes one,
two or three sensors which share the same optical axis. The
U2 can be connected either through a detachable connector
or a pipe fitting for installations with conduit. Refer to the table
below for model numbers and options.
APPLICATION
Each sensor in the U2 has a different response which is
suitable for certain applications.
The UVTRON tube detector has a peak response at 210 nm
and is primarily for gas flame monitoring. This UV detector
using pulse technology is the best for low NOx gas burners
and where a solid state sensor, using flicker technology, does
not provide satisfactory results.
The solid state UV photodiode has a peak response at 310
nm. This sensor is suitable for gas, oil and coal. The principle
of flame monitoring is flicker frequency based. User selectable
high pass filters are used to reject signals that are from
background radiation.
The solid state IR photodiode has a peak response at
1400 nm. This sensor is suitable for low NOx oil and coal
burners, low excess air oil burners, and burners with a limited
view from a windbox front plate. The principle of flame
monitoring is flicker frequency based. User selectable high
pass filters are used to reject signals that are from background
radiation.
Contents
Introduction .......................................................................
Application ........................................................................
Specifications ...................................................................
Approvals ..........................................................................
Installation ........................................................................
Accessories ......................................................................
Operation ..........................................................................
Troubleshooting ................................................................
Communicating Through Modbus ....................................
Manual Setup ................................................................... 13
Automatic Setup ............................................................... 14
Maintenance ..................................................................... 15
Safety Manual ................................................................... 22
Safety Function of the Uniscan 2 ......................... 23
Proof Test Procedure ........................................... 23
Proof Test Interval ................................................ 23
Product Decommissioning ................................... 24