CONTACT TACHOMETER User’s ManUal CT6235B Please read this manual carefully and thoroughly before using this product.
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 . . . . . . . . . . . .
INTRODUCTION Thank you for purchasing General Tools & Instruments’ CT6235B Contact Tachometer. Please read this user’s manual carefully and thoroughly before using the instrument. The CT6235B is a general-purpose instrument that uses dedicated fittings to measure—on contact—the speed of a motor or generator’s rotating shaft and the linear speed of a moving surface such as a conveyor belt or the circumference of a wheel.
KEY FEATURES • Uses contact measurement technique and autoranging • Includes fittings for measuring the speed of a rotating shaft and the linear speed of a conveyor • Wide measurement range and high resolution • Backlit 1 in.
lowed (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 (B) making contact with a surface in linear motion. The surface speed wheel has a 1/8 in.
PRODUCT OVERVIEW Figure 2 shows all of the controls and indicators and other physical features of the CT6235B. Familiarize yourself with their names and locations before continuing. A. Surface speed wheel 1/2" RPM ADAPTER B. 1/2" rubber rpm adapter SURFACE INSERTED IN BLACK SPEED WHEEL PLASTIC SLEEVE (shown inserted in plastic sleeve) B C. Tachometer shaft A D. Measurement button C (on right side) E. Function switch, labeled “m, m/min, rpm” I F. MEM button D G. Display window E H.
SETUP INSTRUCTIONS INSTALL BATTERIES To gain access to the battery compartment, slide its cover in the back of the instrument (callout H of Fig. 2) 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.
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 your flicks, and also how the instrument powers off whenever the Measurement button if released (this “dead man switch” feature extends battery life considerably).
Also note that releasing the MEM button powers 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 three 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.
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 then 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 and then press and hold it again, the display will then show “2”, followed by the value of your second measurement.
Cradle the tachometer in your right hand. While pressing the Measurement button on the right side of the instrument with your right thumb, gently push the cone-tipped end of the rpm adapter into the cavity at the end of the spinning motor or generator shaft whose speed you wish to measure. Take care to keep the two shafts aligned.
Set the function switch to the “m/min” position. Then, cradling the tachometer in your right hand, press the edge of the surface wheel against the moving object whose linear speed you wish to measure. Note that the circumference of the wheel has a 1/8-in.-wide slot into which wire, cable or rope of that diameter fits snugly. Taking care to keep the tachometer perpendicular to the moving conveyor, use the function and MEM buttons to make and store as many measurements of linear speed as you wish.
SPECIFICATIONS Measurement ranges Rotational speeds from 0 to 20,000 rpm; linear speeds from 5cm/min (2 in./min) to 2km/min (6,562 ft/min); lengths from 5cm to 10km (2 in. to 6.2 miles) Measurement accuracy ±0.05% of reading plus one digit Resolutions 0.1 rpm for rpm measurements to 999 rpm, 1 rpm at higher speeds; 0.01m/min for linear speeds up to 99.99 m/min, 0.1m/min at higher speeds; 0.02m over full length measurement range Sampling time 0.
Power source Four “AA” batteries or optional 6V AC/DC converter Current consumption 65mA Operating temperature range 32° to 122°F (0° to 50°C) @ up to 80% relative humidity MAINTENANCE TIPS The CT6235B requires no regular maintenance other than light cleaning of the housing and display with a soft, dry cloth. When the text “LO” appears on the display, it’s time to change the CT6235B’s four “AA” batteries because their total potential has fallen below 4.5 volts.
General Tools & Instruments or to a General-authorized service center, freight prepaid and insured. Acceptance of the exclusive repair and replacement remedies described herein is a condition of the contract for purchase of this product.
GENERAL TOOLS & INSTRUMENTS 80 White Street New York, NY 10013-3567 PHONE (212) 431-6100 FAX (212) 431-6499 TOLL FREE (800) 697-8665 e-mail: sales@generaltools.com www.generaltools.com CT6235B User’s Manual Specifications subject to change without notice ©2011 GENERAL TOOLS & INSTRUMENTS NOTICE - WE ARE NOT RESPONSIBLE FOR TYPOGRAPHICAL ERRORS.
