General PCT2236B User manual

PCT2236B
Please read this manual carefully and thoroughly before using this product.
COMBINATION
CONTACT/
NON CONTACT
LASER TACHOMETER
USER’S MANUAL
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TABLE OF CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Key Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
What’s in the Case. . . . . . . . . . . . . . . . . . . . . . . . . 4 – 5
Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Setup Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Install Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Operating Instructions . . . . . . . . . . . . . . . . . . . . 7 – 15
Simulate Making, Storing and
Recalling RPM Measurements
in Contact Mode. . . . . . . . . . . . . . . . . . . . . . 7 – 10
Measuring Rotating Speeds
in Contact Mode. . . . . . . . . . . . . . . . . . . . . 11 – 12
Measuring Linear Speeds . . . . . . . . . . . . . . . . . 12
Measuring Surface Dimensions . . . . . . . . 12 – 13
Making RPM Measurements in
Non-Contact Mode. . . . . . . . . . . . . . . . . . . 13 – 15
Storing and Recalling RPM Measurements
in Non-Contact Mode. . . . . . . . . . . . . . . . . . . . . 15
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . 16 – 17
Maintenance Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Warranty Information. . . . . . . . . . . . . . . . . . . . . 18 - 19
Return for Repair Policy . . . . . . . . . . . . . . . . . . . . . . 19
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INTRODUCTION
Thank you for purchasing General Tools & Instruments’
PCT2236B Combination Contact/Non-Contact Laser
Tachometer. Please read this user’s manual carefully and
thoroughly before using the instrument.
The PCT2236B is a general-purpose instrument that can
measure the rotational speed of a motor’s or generator’s
spinning shaft using either a contact or non-contact technique.
In non-contact measurement mode, the instrument bounces a
laser beam off a piece of reflective tape that has been affixed to
the shaft and uses an integrated photocell to count the number
of reflections produced per minute. In contact measurement
mode, the instrument uses dedicated fittings that measure the
speed of the shaft by rotating along with it. In contact mode, the
PCT2236B also can measure the linear speed of a moving
surface (such as a conveyor belt or the circumference of a
wheel) and the dimensions of stationary objects.
In both operating modes, measurements are displayed in real
time on a 0.7 in. (18mm) high backlit liquid-crystal display and
stored in memory. Up to 96 measurements of rpm or linear
speed can be stored, indexed and recalled, along with the last
value, the minimum value and the maximum value of a series.
In non-contact mode, the tachometer can measure the speeds
of shafts spinning at up to 99,999 rpm. In contact mode, the
instrument can measure rotational speeds from 0 to 20,000 rpm,
linear speeds from 5cm/min (2 in./min) to 2km/min (6,562
ft./min), and lengths from 5cm to 10km (2 in. to 6.2 miles).
The PCT2236B is powered by four “AA” batteries (included) or
an optional 6V AC/DC adapter.
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KEY FEATURES
• Measures rotational speeds using contact or non-contact
technique
• Autoranging is automatic
• Includes fittings for measuring the speed of a rotating shaft and
the linear speed of a conveyor
• Wide measurement range and high resolution
• Backlit 0.7 in. (18mm) high display supports work in low light
• Stores and indexes up to 96 measurements
• Memorizes the last, minimum and maximum values of a series
of measurements
• Also measures any dimension of a stationary object, in meters
• One-handed operation
• Auto power off function extends battery life
SAFETY INSTRUCTIONS
Spinning shafts and fast-moving conveyor belts can be
dangerous. When using the tachometer, take care not to let your
fingers, hands, hair or clothing make contact with moving parts.
LASER WARNING NOTE!
Do not point laser directly at eye.
Use caution around reflective surfaces.
Keep out of reach of children.
WHAT’S IN THE CASE
The PCT2236B comes fully assembled in a carrying case
along with the following accessories (see Figure 1):
4
•
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• Three rubber fittings—called rpm adapters —for making
contact with the end of a rotating shaft of a motor or
generator. Two have cone-shaped rubber tips that fit into a
hollowed (concave) end of a metal shaft; one (B) has a large
cone compatible with a 1/2 in. diameter shaft, the other (J)
has a smaller cone that fits
into shafts 1/4 in. across. The
third (K) fitting has its own
hollowed end; it is designed
to fit over a 1/4 in. diameter
shaft with a flat or slightly
convex end.
• One rubber/plastic fitting (the
surface speed wheel A) for
making contact with a
surface in linear motion. The
surface speed wheel has a
1/8 in. slot into which moving
wire, cable or rope fits snugly.
• Three 24 in. (6mm) long
strips of 1/2 in. (12mm) wide
adhesive reflective tape
• Three spare Phillips head
screws
• Four “AA” batteries
• This user’s manual
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Fig. 1
1/2" RUBBER RPM ADAPTER
INSERTED IN BLACK PLASTIC SLEEVE
SURFACE
SPEED
WHEEL
1/4" RUBBER
RPM ADAPTER
RPM ADAPTER WITH HOLLOWED END
FOR 1/4" DIAMETER SHAFTS WITH
FLAT OR CONVEX END
(A)
(B)
(K)
(J)
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PRODUCT OVERVIEW
Figure 2 shows all of the controls and indicators and other
physical features of the PCT2236B. Familiarize yourself with
their names and locations before continuing.
A. Surface Speed Wheel
B. 1/2" Rubber RPM Adapter
(shown inserted
in plastic sleeve)
C. Tachometer Shaft
D.
Measurement Button
(on right side)
E. Function Switch, labeled
“
m, m/min, rpm ”
F.
MEM Button
G. Display Window
H. Battery Compartment Cover
(in back)
I. Jack for 6-V AC/DC Adapter
(on left side)
J. 1/4" Rubber RPM Adapter
K. 1/4" Rubber RPM Adapter
with hollowed end
L. Refelctive Tape (on spinning
motor or generator shaft)
M. Reflected Laser Light
(to internal photosensor)
Fig. 2. The PCT2236B’s
controls and indicators
and other physical features
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SURFACE
SPEED WHEEL
C
D
E
F
G
H
K
J
I
B
L
M
A
Fig. 2
1/2" RPM ADAPTER
INSERTED IN BLACK
PLASTIC SLEEVE
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SETUP INSTRUCTIONS
INSTALL BATTERIES
To gain access to the battery compartment, remove the
Phillips head screw securing its cover in the back of the
instrument (callout H of Fig. 2). Slide the cover down and away
from the unit. Then install four “AA” batteries in the correct
orientation, using the polarity marks on the inside of the
compartment as a guide. Don’t forget to install the batteries
over the ribbon, which makes it easier to remove them later.
Replace the battery compartment cover, tucking the end of the
ribbon under it, and secure it with the Phillips head screw.
OPERATING INSTRUCTIONS
SIMULATE MAKING, STORING AND RECALLING RPM
MEASUREMENTS IN CONTACT MODE
Before using the PCT2236B on actual equipment, General
suggests that you familiarize yourself with the way the
instrument measures, stores and recalls speeds by spinning
the tachometer’s shaft by hand. By simulating readings you
can expect to see in practice, you will safely gain expertise
that will save you time later.
To get started, make sure the black plastic sleeve (see
Fig. 1 (B) ) is installed on the tachometer’s shaft (callout C of
Fig. 2), with the slot of the sleeve over the shaft’s metal pin.
Cradle the tachometer in your right hand. Move the function
switch (callout E of Fig. 2) to either the “ m/min ” or “ rpm ”
position. Then press the Measurement button o n the right
side of the instrument (callout D of Fig. 2) with your right
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thumb. Note that this illuminates the display window. The
display should show “ 0 ”, either with the letters “ rpm ” directly
below it or with the letters “ m/min ” below it to the left,
depending on the position of the function switch.
To simulate a speed measurement , keep the tachometer
cradled in your right hand and spin its shaft by “flicking” it
with the middle two fingers on your left hand while pressing
the Measurement button with your right thumb. Note how
the display tracks the force of yo
ur flicks, and also how the
instrument powers off whenever the Measurement button
if released (this “dead man switch” feature extends batt
ery
life considerably).
To simulate storing measurements , keep the
Measurement button dep ressed with your right thumb while
you make three simulated speed measurements, as follows:
• Flick the shaft with your left index finger once. Store the
displayed reading by pressing the MEM button w ith your
left thumb.
• Flick the shaft again to make another simulated
measurement. Store this reading by pressing the MEM
button aga in.
• Flick the shaft a third time and store the third reading as
well by pressing the MEM button.
After simulating and storing three measurements, release
the Measurement button and do not press it again until
instructed to.
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To simulate recalling stored measurements , press the
MEM button once and hold it. This illuminates the display,
which now shows the highest of the three readings you have
just stored. Note that if you continue
holding the
MEM button , the display
alternates between showing the highest
value and the letters “ UP ”, signifying the
maximum speed.
Also note that releasing the MEM button
pow
ers off the display and the instrument.
Now press the MEM button twice and
hold it. This again illuminates the display,
but now it shows the last reading you stored, indicated by and
alternating with the letters “
LA ”.
Finally, press the MEM button th ree times and hold it. This
retrieves the slowest of the three speeds you measured and
stored. This value is shown alternating with the letters “ dn ”,
signifying the minimum speed.
To try out other memory-related features,
you can now press the Measurement
button o n the right side. Now press the
MEM button once, twice and three times (holding it in each
time) and note from the display that all three of your stored
measurements have been erased (indicated by “
0.0 ” readings
for UP , dn and LA ). You can confirm this by pressing and holding
the MEM button until the display begins counting down from
20. When the count reaches 0, the display immediately switches
to showing the letters “ AN ” on the left side and a number (in
this case, “ 0 ”) on the right. (The letters “ AN ” are an
abbreviation for the Ancient Greek word for “recall.”)
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To complete this simulation exercise and put your new
expertise to the test, make and store a set of five simulated
measurements by hand-spinning the tachometer’s shaft and
using the MEM button. Then , remembering not to press the
Measurement button, press and hold the MEM button as
ma
ny times as needed to make the display go into countdown
mode.
Note that because you have stored five measurements, the
display will read “ AN 5 ” once the countdown reaches zero. If
you release the MEM button and th en press and hold it again,
the display will first read “ 1 ” and then the value of the first of
the five measurements you stored. If you release the MEM
button an d then press and hold it again, the display will then
show “ 2 ”, followed by the value of your second measurement.
Release, press and hold again, and the display will show “ 3 ”,
followed by the value of your third measurement. By repeating
this sequence, you can retrieve up to 96 measurements in the
order in which they were stored. Once all of the stored
measurements have been displayed, the tachometer will
return to the mode in which pressing the MEM button once,
twice or three times calls up the minimum, maxim
um and
last values of the set of measurements you have stored.
With this simulated experience under your belt, you can now
confidently measure the rotational speed of a spinning motor or
generator shaft, or the linear speed of virtually any conveyor
belt.
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