What Is a Meter Min Max Mode?

As an Amazon Associate we earn from qualifying purchases.

MIN MAX mode is a recording function. While it runs, the meter keeps track of the lowest and highest readings it sees, so you can check a value that changes too quickly to read by eye. Some meters also offer a faster capture mode for short events. The Fluke article we opened describes both the normal min/max function found on many multimeters and a faster version on certain Fluke models.

Quick answer

• MIN MAX records the lowest and highest readings during a monitoring session.
• It helps when a signal moves too fast to read or when you are not present to watch it.
• On some Fluke models, a FAST MN/MX or Peak Min/Max function captures shorter events.
• Those faster functions are limited to voltage and current measurement, according to the article.

What the recording does

A normal recording tracks two values: the minimum and the maximum seen since the mode started. You read the result on the display after the signal has moved. This is useful for checking whether a voltage dips under load, or whether a reading drifts above a limit while you are away from the meter.

Fast and peak capture on Fluke meters

The Fluke article describes the Fluke 187, Fluke 189 and Fluke 87V as models with a faster recording function. The article says these functions allow users to capture much faster signal events than the normal min/max function found on many DMMs. It also says the FAST MN/MX (187, 189) or Peak Min/Max (87V) function “is restricted to the voltage and current measurement.” It can be used to capture intermittent or transient events that occur when you are not watching the meter.

How to start the recording

The article gives the steps for these Fluke models. Select the meter function for the signal you want to monitor, then attach the probes to the test points. On the 187 and 189, press SHIFT and then MIN MAX once to start FAST MN/MX. On the 87V, press MIN MAX and then the continuity button once to start Peak Min/Max. The display then shows a MAX symbol with the present maximum value, and the meter stays in the range set for the measurement while recording.

Check the manual for your own meter before you copy these steps. Button labels and sequences differ between models, and the article is about specific Fluke models only.

What the readings show

• On the 187 and 189, the meter timestamps the highest, lowest and average values, so you can see when each one occurred.
• The 187 and 189 show elapsed time while recording. The article notes that the 87V does not have this clock.
• When monitoring AC voltage or current with the peak function, the display shows peak values for the minimum and maximum readings, and the article says the RMS value appears for the average on the 187 and 189.

Common mistakes

• Expecting FAST MN/MX or Peak Min/Max to work for resistance or other functions. The article limits it to voltage and current.
• Reading peak values as if they were ordinary RMS readings. Check how the meter labels each value.
• Forgetting when you started a recording on a meter without a clock. The article suggests noting the start time or using stored readings where the meter has them.

Safety first

A recording function does not change electrical safety. Check the meter’s CAT rating and voltage rating against the circuit before you connect the probes. Work on mains circuits can kill, and panel or service work belongs to a licensed electrician. The article itself says to read the instruction manual and follow all safety precautions before using these functions.

How we chose

This post answers one question: what MIN MAX recording does and how the fast capture function on certain Fluke models differs. It uses the single Fluke article listed in Sources, which we opened on 2026-10-27. It does not compare brands or rank meters, and it adds no figures that the article does not state.

What we could not verify

The Fluke article does not describe how every multimeter brand implements MIN MAX, and it does not give recording times for the normal function. The sources we opened do not give a rule for setting a limit on a recording. This post does not make those claims.

Frequently asked questions

Can FAST MN/MX measure resistance?

No. The Fluke article says the FAST MN/MX (187, 189) or Peak Min/Max (87V) function is restricted to voltage and current measurement.

Does the 87V show elapsed time?

No. The article says the Fluke 87V does not have the elapsed time clock capability.

Does the 187 or 189 record average values?

Yes. The article says these models timestamp the highest, lowest and average values.

Where do I find the exact button steps?

Use the manual for your own model. The article warns that the steps are for the models it covers, and button sequences differ between meters.

Bottom line

MIN MAX records the lowest and highest readings so you can review a changing signal. Use it when a value moves too quickly to read or when you cannot watch the meter. Check your model’s manual for the exact button sequence and the functions it supports.

Related guides

• Best multimeters for home use, for a general starting point with basic features.
• Best multimeters for AC voltage, for meters that handle AC readings.

Sources

• Fluke, “Under-utilized functions: How to use fast/peak min/max on your DMM,” https://www.fluke.com/en-us/learn/blog/digital-multimeters/under-utilized-functions-how-to-use-fast-peak-min-max-on-your-dmm (opened 2026-10-27)