Fluke 45 user manual Hold Touch Hold Modifier, MN MX Minimum Maximum Modifier

Operating the Meter From the Front Panel	3
Selecting A Function Modifier

HOLD (Touch Hold) Modifier

The Touch Hold modifier allows you to take a measurement and "hold" that measurement on the display. This feature can be particularly advantageous in difficult or hazardous circumstances when you might want to keep your eyes fixed on the probes, and then read the display when it is safe or convenient to do so. When a new, stable reading is detected, a beep is emitted, and the display is automatically updated.

Press Hto select the Touch Hold modifier. When Touch Hold is selected, "HOLD" is shown in the primary display. In Touch Hold, each press of Hforces a new reading to be displayed. To exit Touch Hold, press down Hfor two seconds.

If you are in the autorange mode when Touch Hold is selected, you will autorange to the correct range. If you are in the manual range mode, you will enter Touch Hold in the selected (fixed) range you were in when Touch Hold was selected.

The Touch Hold modifier can be combined with the MN MX modifier to hold and update only when a new minimum or maximum value is detected. Pressing Hless that two seconds when Touch Hold has been selected forces the display to update.

The meter allows you some choice when it comes to determining the minimum response level needed for Touch Hold to capture and display a measurement. You can choose among three Touch Hold sensitivity levels:

•Level 1 (5 % of range)

•Level 2 (7 % of range)

•Level 3 (8 % of range)

To change this level, press S, then press H. The number “1,” “2,” “ or “ 3 “appears on the primary display. Press Uor Tto step to the desired sensitivity level. Then press Eto set the level and return the primary display. You can return to the primary display without changing the sensitivity level by pressing any button except E, U, or T.

MN MX (Minimum Maximum) Modifier

The MN MX modifier causes the meter to store the minimum and maximum inputs measured since the MN MX modifier was selected.

Press Jto select the MN MX modifier. When the MN MX modifier is first selected, the minimum and maximum values are set to the displayed reading and the "MIN" annunciator lights. Press Jagain to display the maximum reading (and the "MAX" annunciator). Each subsequent press of the Jbutton toggles between the minimum and maximum measurements taken. To exit the MN MX modifier, press and hold down the

Jbutton for two seconds.

Selecting the MN MX modifier turns off autoranging and locks in the present range. Make sure you are in the correct range before selecting the MN MX modifier. If you press Uor Tafter MN MX has been selected, you will automatically exit the MN MX modifier.

To observe the quantity being measured without resetting the stored MN MX values, use the secondary display by pressing S, then select the same measurement function that is selected for the primary display.

Using Function Modifiers in Combination

The meter allows you to use multiple function modifiers (dB, REL, HOLD, MN MX) simultaneously. The selected modifiers are evaluated in the following order: HOLD, dB, MN MX, and REL. That is, the meter first looks for a stable measurement for Touch

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