Slack Chain Detection0 pages

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BRAIME
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4B BRAIME ELEVATOR COMPONENTS LIMITED - Hunslet Road, Leeds LS10 1JZ, UK
Tel: +44 (0)113 246 1800 Fax: +44 (0)113 243 5021 Email: 4b-uk@go4b.com
Speed Relay
Slack - Broken Chain Detector
The 4B high power WDA reluctance sensor will detect a moving ferrous object up to 4” away. It is not affected by dust or material build up. It
can be used as a slack/broken chain detector when installed as shown below. The sensor has an adjustable sensing range (1” – 4”) and an
LED helps with field adjustment.
Using the mounting block supplied, cut a 4” diameter hole in the sheet metal and position the mounting block so that the sensor is centered on
this hole. Alternatively, the sensor and mount can be installed on a stainless steel plate without drilling a hole for the sensor. In this case, the
sensor will not be affected because the sensing field can pass through the stainless steel plate.
WARNING - Make sure that there is no ferrous steel (such as the machine’s frame) within the sensing field.
WDA Sensor
(WDA3V34C)
WDA High Temperature Sensor
(HTAS1V34)
Target or Bolt – 3/8” dia
1 – 3”
WDA - High Power
Reluctance Sensor
Sensitivity
Adjustment
LE
D
Speed
Relay
Contacts change
state when sensor
stops detecting
target or bolt.
Plastic
Paddle
Steel Flight
OPTION 1
Sensor Detecting Bolt Installed on the Paddle
Under normal running conditions, the target bolt
passes through the sensor’s field and a pulse is
sent to the speed relay. If the chain becomes
slack, the target bolt will drop below the field and
the pulses will stop, causing the relay contact to
change state.
OPTION 2
Sensor Detecting Steel Flight
Under normal running conditions, the steel flight
passes through the sensor’s field and a pulse is
sent to the speed relay. If the chain becomes
slack, the steel flight will drop below the field and
the pulses will stop, causing the relay contact to
change state.
OPTION 3
Sensor Waiting to Detect Steel Flight
Under normal running conditions, the steel flight
is out of the sensor’s field, so no pulses are sent
to the speed relay. If the chain becomes slack,
the steel flight comes into the sensor’s field and
a pulse is sent to the speed relay, causing it to
change state.
To Speed Relay
To Speed Relay
1 – 3”
1 – 3”
1”
Detailed specification, wiring diagrams and
installation/operating instructions available
immediately upon request.
Please refer to instruction manual for correct installation.
Information subject to change or correction. August 2010.