Model 407850 Version 1.2 December 2005

4

Zero Adjustment Procedure

Please perform a zero calibration before each use. This will ensure the highest accuracy.

Note: If the meter is used for a long period of time, temperature change and battery power

loss may cause the zero calibration to drift. For continued precision measurement, the

meter’s zero calibration should be readjusted.

1.

Set the ACC/VEL switch to the ACC (Acceleration) position.

2.

Insure that there is no signal present at the vibration sensor.

3.

Remove the protective rubber holster and open the battery cover (described below).

4.

Use a screwdriver to adjust the “Zero adjust VR5” potentiometer until the display

reads 0000.

Data Hold

To freeze the LCD display, press the HOLD key. The 'D.H.' hold icon will appear at the top

of the LCD. Press the HOLD key again to return to normal operation (the 'D.H.' hold icon

will switch off).

MIN / MAX RECORD / RECALL Modes

To begin capturing the Minimum (MIN) and Maximum (MAX) vibration values, press the

RECORD key (‘REC’ will appear on the LCD). After taking measurements in the RECORD

mode, press the RECALL button. ‘MAX’ will appear on the display along with the highest

reading recorded since the RECORD button was pressed. Press the RECALL button again

to view the lowest reading (‘MIN’ will appear on the display). To return to normal operation,

press the RECORD button. ‘REC’ will switch off indicating that the meter has returned to

the normal mode.

RS-232 Serial PC Interface

The meter is equipped with an RS-232 serial data port (located at the top of the meter next

to the probe input jack). This interface was designed to operate with the Extech Data

Acquisition Software (PN 407001) and enables the user to capture, store and display

readings on a PC. For more information, contact Extech or refer to the 407001 user

manual for details.

VR5

Rear View of 407850

Battery Compartment