Safeline Signature, Operating And Instruction Manual

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OPERATING INSTRUCTIONS
4618 - 021 109
SPEED SENSOR FOR THE TM3 AND TM3[G] TIMERS
Speed Sensor Requirements
The speed sensor may be:
a) A purpose bought item, known as a Rotary
Encoder,
or
b) A Proximity/Photo-electric sensor together
with the necessary hardware to produce a
pulse output from rotary movement.
In either case the device must be coupled up to the
conveyor drive system to give a pulse output signal in
direct relation to the distance moved by the conveyor.
The device chosen must have the following
electrical specification:
Operating Voltage- +15 V D.C.
Quiescent Current - 60 mA maximum.
Output Type - NPN open collector.
PNP output devices can be accommodated by
changing the internal link arrangement in the detector
head.
Note
If a pack sensor is also being used, both the pack
sensor and the speed sensor must be the same
output type, NPN or PNP.
Output Voltage:- 15 V minimum.
Output Current:- 10 mA minimum.
Output Waveform:- Pulse output
Pulse width:- 10 ms minimum.
Frequency:- 50 Hz maximum
Speed Sensor Electrical Connections
Refer to the Installation section.
Connect the sensor to the terminals labelled Speed
Sensor.
Producing A Rotary Encoder Using A
Proximity or Photo-electric Sensor
Fig 24 Rotary Encoder
Figure A-1above shows a possible technique for
producing a rotary encoder using a proximity or photo-
electric sensor.
The disk shown has been drilled so that the sensor
will give a pulse output as the rotating disk
intermittently interrupts its sensing area.
The sensor shown would typically be a proximity type
and the disk would be fabricated from mild steel.
Alternatively a two part photo-electric sensor could be
used, i.e with separate transmitter and receiver or with
combined transmitter and receiver and reflector.
Note
Avoid the use of photoelectrics that require the disk
itself to reflect the beam.