Tachometer

Tachometer

PURPOSE

To lay down a procedure for Cleaning, Operation and Calibration of Tachometer.

SCOPE

This procedure is applicable for the Cleaning, Operation and Calibration of Tachometer screw in Quality assurance Department.

REFERENCE(S) & ATTACHMENT(S)

REFERENCE

In-House

CROSS REFERENCE DOCUMENTS

NA

ATTACHMENTS

Attachment/Annexure/Formats

NA

DEFINITION & ABBREVIATION(S)

 DEFINITION

TACHOMETER: A tachometer is an instrument which is used to measure the speed of an object or substance, it is also called as a revolution counter.

ABBREVATIONS

LCD : Liquid crystal display

V  : Volt

RPM: Rotation per minute

Mm :  Millimeter

RESPONSIBILITY

QA Department Person:

To used instrument as per defined procedure

PROCEDURE

SAFETY/PRECAUTION/EHS

Always use calibrated instrument.

Cleaning Procedure

Clean the Tachometer before & after each use.

Clean the Tachometer with the help of dry, clean, lint free cloth.

Operating Procedure

Place a small piece of reflective tape (included) on the shaft or moving element (disc, pulley, etc.) whose speed is to be measured. If the element’s surface is highly reflective it
may need to be painted a darker color in order to ensure reliable results. If the distance to the object is less than 5″ (127 mm), reflective tabs (optional) should be used instead of
reflective tape.

Aim the tachometer at the reflective tape from a distance of 2 to 10 inches.

Depress the measure button for 1-2 seconds to observe the display as it changes according to the speed of the shaft or rotating element (as soon as the laser hits the reflective tape, the unit will start to indicate the speed). If the beam is “on target” the unit RPM will flash at the top of the display. If RPM is not flashing then the beam is “off target” (adjust aim).

After observation is completed, retain the reading by releasing the power switch before removing the tachometer from its position. The last reading is displayed for a period of 5
minutes and can be extended any number of additional 5 minute increments by pressing the memory switch.

Calibration Frequency

Calibration shall be performed by outside party & Calibration Frequency: Yearly (± 30 days )

Precautions

The non-reflective area must always be greater than the reflective area.

Shaft surface must be clean and smooth before applying reflective tape.

If measuring the very low RPM values, for that purpose attach more “Reflective marks” averagely. Than divided the reading shown by the number of “Reflective marks” to get the real RPM.

Always remove the batteries after use.

Replacement of battery :

When the left corner of LCD display show “” , it is necessary to replace the battery However, in –spec measurement may still be made for several hours after low battery indicator appears before the instrument become inaccurate.

Slide the battery cover away from the instrument and remove the battery. Replace with 9V battery and reinstate the cover. Make sure the battery cover is secured change the battery.

REVISION HISTORY: