MM 2 - Multimeter BENNING - Free user manual and instructions

Product Type	Digital Multimeter
Brand	BENNING
Model	MM 2
Display	LCD 3½ digit, 20 mm height, max 1999
Number of measurements per second	2.5
Measurement functions	DC/AC voltage, DC/AC current, resistance, diode test, continuity test, capacitance, frequency
DC voltage ranges	200 mV to 600 V, resolution 0.1 mV to 1 V, accuracy ±(0.5% + 2 digits)
AC voltage ranges	200 mV to 600 V, resolution 0.1 mV to 1 V, accuracy ±(1.3% + 5 digits) (40-500 Hz)
DC current ranges	200 µA to 20 A, resolution 0.1 µA to 10 mA, accuracy ±(1.0% to 2.0% + 2-3 digits)
AC current ranges	200 µA to 20 A, resolution 0.1 µA to 10 mA, accuracy ±(1.5% to 2.5% + 3-5 digits) (40-500 Hz)
Resistance ranges	200 Ω to 20 MΩ, resolution 0.1 Ω to 10 kΩ, accuracy ±(0.8% to 2% + 2-5 digits)
Diode test	Open circuit voltage max 3.2 V, measuring current max 1.5 mA, accuracy ±(1.5% + 5 digits)
Continuity test	Threshold resistance < 50 Ω, audible beep
Capacitance ranges	2 nF to 200 µF, resolution 1 pF to 100 nF, accuracy ±(3.0% + 4 digits)
Frequency ranges	2 kHz to 200 kHz, resolution 1 Hz to 100 Hz, accuracy ±(1.5% + 5 digits)
Power supply	1 9 V battery (IEC 6 LR 61)
Battery life	Approximately 150 hours (alkaline)
Dimensions (without frame)	175 x 84 x 31 mm
Dimensions (with frame)	192 x 95 x 50 mm
Weight (without frame)	340 g
Weight (with frame)	550 g
Overvoltage category	CAT II 600 V, CAT III 300 V
Protection	Double insulation (class II), IP30
Operating temperature	0 °C to 50 °C (depending on humidity)
Storage temperature	-20 °C to +60 °C (battery removed)
Protective fuses	1 A/500 V (ref. 749669) and 16 A/500 V (ref. 749770) fast-acting
Supplied accessories	Safety measuring leads (red/black 1.4 m), rubber holster, carrying case, 9 V battery, mounted fuses, user manual
Maintenance	Clean with dry cloth, no solvents; replace battery when symbol appears; replace defective fuses with identical parts

Frequently Asked Questions - MM 2 BENNING

How to measure DC voltage with the BENNING MM 2?

Select the voltage range with the rotary switch, then choose DC with the selector. Connect the black lead to the COM jack and the red lead to the V/Ω/Hz jack. Place the probes on the measurement points and read the display.

How to measure AC current up to 20 A?

Set the rotary switch to the AC current range (A~) and select AC. Connect the black lead to COM and the red lead to the 20 A jack. Open the circuit and insert the multimeter in series. Caution: measurement time < 30 seconds, then pause for 3 minutes.

How to test continuity of a wire?

Turn the rotary switch to the diode/continuity symbol (▶)). Connect the leads to COM and V/Ω/Hz. Touch the two ends of the wire. If the resistance is less than 50 Ω, an audible beep sounds.

How to measure resistance?

Select the Ω range with the rotary switch. Connect the black lead to COM and the red lead to V/Ω/Hz. Place the probes on the resistor. Read the value on the display. Caution: do not measure on a live circuit.

How to test a diode?

Set the rotary switch to the diode symbol (→). Connect the leads to COM (black) and V/Ω/Hz (red). Connect the red probe to the anode and the black to the cathode. A silicon diode under forward bias displays between 0.5 and 0.9 V. A '1' display indicates open, '000' indicates short circuit.

How to measure capacitance?

Select the capacitance range with the rotary switch. Fully discharge the capacitor before measurement. Insert it into the capacitance jacks (⑥) respecting polarity. Read the value. Never apply voltage to these jacks.

How to replace the battery of the BENNING MM 2?

Switch off the device and remove the leads. Remove the rubber holster. Unscrew the 3 screws on the back. Lift the bottom of the case. Disconnect the old battery and replace with a new 9 V (IEC 6 LR 61). Reassemble in reverse order.

How to replace a fuse?

Disconnect power and remove the leads. Remove the holster and open the case as for battery replacement. Lift the circuit board. Replace the defective fuse with an identical fuse (1 A/500 V ref. 749669 or 16 A/500 V ref. 749770). Reassemble.

What safety precautions should be observed?

Never measure on circuits exceeding 600 V relative to earth. Use cables in good condition. Before opening the device, switch it off. Do not exceed specified overvoltage categories (CAT II 600 V, CAT III 300 V). If in doubt, consult a specialist.

What to do if the display shows '1' or '-1'?

A '1' or '-1' display indicates an overrange: the measured value is too high for the selected range. Switch to a higher range using the rotary switch. If the problem persists, check the circuit or leads.

USER MANUAL MM 2 BENNING

Multilingual manuals on included CD and at

BENNING MM 3

-1.08.0 OFF DC AC 20μF 200μF 200μA 200μA 200μA 2K Hz 20K Hz 200kΩ 20kΩ 200mV 20MΩ 200mV 600V 200V 2V 200mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA 20mA - + + 20 A μAmA COM VΩ Hz MAX 10A cm. 28A 184w. F/65D MAX (58mA) P/65D CAT II MX NVR BENNING MM 3

18.8.8 -18.8.8 OFF 200μF 600V 200V 20V 200mV 20MΩ 2MΩ 200kΩ 20kΩ 2K Hz 20K Hz 200K Hz - + 20 A μAmA COM VΩ Hz MAX 15A cc/Hz, 25A 50rec, FUSED MAX 250mA FUSED CAT II MAX 600 V BENNING MM 3

Bild 1: Gerätefrontseite
Fig. 1: Front tester panel
Fig. 1: Panneau avant de l'appareil
Fig. 1: Parte frontal del equipo
Obr.1: Přední strana přístroje
ill. 1: Lato anteriore apparecchio
Fig. 1: Voorzijde van het apparaat
Rys.1: Panel przedni przyrządu
Imaginea 1: Partea frontală a aparatului
Рис. 1. Фронтальная сторона прибора
Fig. 1: Framsida
Res. 1: Cihaz ön yüzü

-18.88 BENNING AM 3 + - A B

Fig. 2: Direct voltage measurement

Fig. 2: Mesure de tension continue

Fig. 2: Medición de tension continua

Fig. 3: Alternating voltage measurement

Fig. 3: Mesure de tension alternative

Fig. 4: DC current measurement

Fig. 5: AC current measurement

Fig. 6: Resistance measurement

Fig. 8: Continuity Testing with buzzer

Fig. 9: Capacity Testing

Fig. 10: Frequency measurement

Technical line drawing of a device casing with internal components and mounting holes (no text or symbols)

Fig. 11: Battery replacement

Fig. 11: Cambio de pila

Exploded view diagram of a multimeter with labeled components (no text or symbols on the diagram itself)

Fig. 13: Winding up the safety test leads

Fig. 14: Erecting the BENNING MM 3

Fig. 14: Installation du BENNING MM 3

Digital Multimeter for

• DC voltage measurement
• AC voltage measurement
• DC current measurement
• AC current measurement
• Resistance measurement
• Diode testing
• Continuity testing
• Capacitance measurement
• Frequency measurement

Index of Contents

1. Operating instructions
2. Safety instructions
3. Scope of delivery
4. Meter description
5. General Specifications
6. Ambient Conditions
7. Electrical Specifications
8. Measuring with BENNING MM 3
9. Maintenance
10. How to use the protective rubber holster
11. Technical data of the measuring accessories
    12.Environmentalnote

1. Operating Instructions

This operating manual is intended for

• electrical professionals
• qualified electrotechnical persons

The BENNING MM 3 is designed for measuring in dry conditions. It must not be used on electrical circuits with a rated voltage greater than 600 V AC/DC (for details refer to "Ambient Conditions" section).

The following symbols appear in this manual and on the BENNING MM 3:

This symbol indicates dangerous voltage.

This symbol indicates warnings and cautions to be observed when using the BENNING MM 3 (refer to manual!)

This symbol on the BENNING MM 3 indicates that the BENNING MM 3 has double insulation (Protection Class II)

This symbol on the BENNING MM 3 indicates the unit contains built-in fuses.

This symbol appears in the display when the battery is low.

This symbol indicates the "Continuity testing" mode is selected. The buzzer sounds for acoustic test results.

This symbol indicates the "Diode testing" mode is selected.

(DC) Direct voltage or current.

(AC) Alternating voltage or current.

Ground (voltage against earth)

Capacitor (terminals)

2. Safety note

The instrument is built and tested in accordance with

DIN VDE 0411 part 1/ EN 61010-1

DIN VDE 0411 Part 2-033/EN 61010-2-033

DIN VDE 0411 Part 031/EN 61010-031

and has left the factory in perfectly safe technical condition.

To maintain this condition and ensure safe operation of the multimeter, the user must observe the notes and warnings given in these instructions at all times. Improper handling and non-observance of the warnings might involve severe injuries or danger to life.

WARNING! Be extremely careful when working with bare conductors or main line carrier! Contact with live conductors will cause an electric shock!

The unit may be used only in power circuits within the over-voltage category II with a conductor for 600 V max. to earth, or within overvoltage category III with a conductor for 300 V against ground.

Only use suitable measuring leads for this. With measurements within measurement category III, the projecting conductive part of a contact tip of the measuring leads must not be longer than 4 mm.

Prior to carrying out measurements within measurement category III, the push-on caps provided with the set and marked with CAT III and CAT IV must be pushed onto the contact tips. The purpose of this measure is user protection.

Remember that work on electrical components of all kinds is dangerous. Even low voltages of 30 V AC and 60 V DC may be dangerous to human life.

Before starting the multimeter up, always check it as well as all cables and wires for signs of damage.

Should it appear that safe operation of the multimeter is no longer possible, it should be shut down immediately and secured to prevent it being switched on accidentally.

It may be assumed that safe operation is no longer possible:

- if the instrument or the measuring leads show visible signs of damage, or

- if the multimeter no longer functions, or

- after long periods of storage under unfavourable conditions, or

- after being subjected to rough transport.

In order to avoid danger,

- do not touch the bare prod tips of the measuring leads,

- insert the measurement leads in the appropriately designated measuring sockets on the multimeter

3. Scope of delivery

The following items are included in the delivery of a BENNING MM 3:

3.1 one BENNING MM 3

3.2 one safety test lead, red (L=1.4 m)

3.3 one safety test lead, black (L=1.4 m)

3.4 one protective rubber holster

3.5 one compact protective carrying case

3.6 one 9 V battery and two different fuses (built into unit)

3.7 one operating manual

Note on replaceable parts :

- The BENNING MM 3 contains fuses for overload protection :

One fast blow fuse rated 16 A (500 V), D = 6.35 mm, L = 32 mm (part no. 749770) and one fast blow fuse rated 1 A (500 V), D = 6.35 mm, L = 32 mm (part no. 749669).

- The BENNING MM 3 is powered by a built-in 9 V block battery (IEC 6 LR 61).

4. Tester description

refer to figure 1 front tester panel

The display and operating elements shown in figure 1 are denoted as follows:

① Digital display for measurement values, display for overrange indication,

② Polarity display,

③ Battery indicator, appears when the battery is low,

4 Selector switch for direct voltage (DC) or alternating voltage (AC),

5 Rotary switch for function and range selection

⑥ Terminals for capacitance measurements

⑦ Input terminal (positive ^1 ) for V, W and Hz,

8 COM-Terminal, common return terminal for current, voltage, resistance and frequency measurements, continuity and diode tests,

9 Input terminal (positive) for mA/mA range, for currents up to 200 mA,

10 Input terminal (positive) for 20 A range, for currents up to 20 A,

11 Protective rubber holster

1) the automatic polarity display for direct and alternating current refers to this terminal

5. General Specifications

5.1 General specifications for the BENNING MM 3

5.1.1 The digital display is a 312 digit liquid crystal display with 20 mm digit height and automatic decimal point placement. The highest display value is 1999.

5.1.2 The polarity display ② is automatic. As positive is implied by the defined input terminal, only a negative pole will be indicated with "-".

5.1.3 Overranging is indicated by "1" or "-1".

5.1.4 The measuring rate of the BENNING MM 3 is a nominal 2,5 readings per second rate.

5.1.5 The BENNING MM 3 is turned on and off using the rotary switch ⑤. Unit is turned off when switch is in "OFF" position.

5.1.6 The BENNING MM 3 powers off automatically after approx. 30 minutes. It can be powered on again by turning the rotary switch ⑤ to select another range.

5.1.7 Temperature coefficient of the measurement reading: 0.15 x (given accuracy)/ °C, < 18 °C or > 28 °C.

5.1.8 The BENNING MM 3 is powered by a 9 V block battery (IEC 6 LR 61).

5.1.9 When the battery voltage drops below the operating voltage of the BENNING MM 3 a low battery symbol appears in the display.

5.1.10 The lifespan of a battery is approx. 150 hours (Alkaline battery).

(L x W x H) = 175 x 84 x 31 mm without protective rubber holster (L x W x H) = 192 x 95 x 50 mm with protective rubber holster Meter weight: 340 g without protective rubber holster 550 g with protective rubber holster

5.1.12 The safety test leads provided with the meter are specifically suited for the rated voltage and current of the BENNING MM 3. The probe tips can be covered with protective caps.

5.1.13 The BENNING MM 3 is protected from mechanical damage by a protective rubber holster ⑪. The protective rubber holster ⑪ allows the BENNING MM 3 to be placed upright or hung up during measuring.

6. Ambient conditions

- The BENNING MM 3 is designed for measuring in dry conditions,

- Altitude during measuring: 2000 m maximum

- Overvoltage category/ Location category: IEC 60664-1/ IEC 61010-1 → 300 V category III, 600 V category II,

- Pollution degree : 2,

- Protection Class: IP 30 (DIN VDE 0470-1 IEC/ EN 60529)

IP 30 means: Protection against access to dangerous parts and protection against solid impurities of a diameter > 2.5 mm, (3 - first index). No protection against water, (0 - second index).

- Working temperature and relative humidity:

for working temperature between 0 °C and 30 °C : relative humidity smaller than 80 %

for working temperature between 30 °C and 40 °C : relative humidity smaller than 75 %

for working temperature between 40 °C and 50 °C : relative humidity smaller than 45 %

- Storage temperature: the BENNING MM 3 can be stored at temperatures between -20 °C and +60 °C. The battery should be removed when tester is in storage.

7. Electrical specifications

Note: measurement accuracy is given as the sum of

- a relative percentage of the reading and

- the number of least significant digits

This accuracy is valid for temperatures between 18 °C and 28 °C, with a relative

humidity smaller than 75 %.

7.1 Direct voltage ranges

The input impedance is 10 MΩ.

Range	Resolution Accuracy	Overload protection
200 mV	100 μV ± (0,5 % of reading + 2 digits) 600 V	rms
2 V	1 mV ± (0,5 % of reading + 2 digits) 600 V	rms
20 V	10 mV ± (0,5 % of reading + 2 digits) 600 V	rms
200 V	100 mV ± (0,5 % of reading + 2 digits) 600 V	rms
600 V	1 V ± (0,5 % of reading + 2 digits) 600 V	rms

7.2 Alternating voltage ranges

The input impedance is 10 MΩ parallel 100 pF. The measurement value is arrived at by average sensing and is displayed as the RMS value.

Range	Resolution	Accuracy in 40 Hz - 500 Hz frequency range	Overload protection
200 mV	100 μV ± (1,3 % of reading + 5 digits)	600 V	rms
2 V	1 mV ± (1,3 % of reading + 5 digits)	600 V	rms
20 V	10 mV ± (1,3 % of reading + 5 digits)	600 V	rms
200 V	100 mV ± (1,3 % of reading + 5 digits)	600 V	rms
600 V	1 V ± (1,3 % of reading + 5 digits)	600 V	rms

7.3 Direct current ranges

Overload protection:

• 1 A (500 V) fast blow fuse on μA/ mA input terminal
• 16 A (500 V) fast blow fuse on 20 A input terminal

Current measurements in the 20 A range must last for 30 seconds maximum followed by a 3 minute break, 10 A continuous.

Range	Resolution	Accuracy	Burden Voltage
200 μA	0,1 μA ± (1,0 % of reading + 2 digits)		600 mV max.
2 mA	1 μA	± (1,0 % of reading + 2 digits)	600 mV max.
20 mA	10 μA	± (1,0 % of reading + 2 digits)	600 mV max.
200 mA	100 μA ± (1,0 % of reading + 2 digits)		900 mV max.
20 A	10 mA	± (2,0 % of reading + 3 digits)	900 mV max.

7.4 Alternating current ranges

The measurement value is arrived at by average sensing and is displayed as the RMS value.

Overload protection:

• 1 A (500 V) fast blow fuse on A/ mA input terminal
• 16 A (500 V) fast blow fuse on 20 A input terminal

Current measurements in the 20 A range must last for 30 seconds maximum followed by a 3 minute break, 10 A continuous.

Range	Resolution	Accuracy in 40 Hz - 500 Hz frequency range	Burden Voltage
200 μA	0,1 μA	± (1,5 % of reading + 3 digits) 600 mV	rms max.
2 mA	1 μA	± (1,5 % of reading + 3 digits) 600 mV	rms max.
20 mA	10 μA	± (1,5 % of reading + 3 digits) 600 mV	rms max.
200 mA 100 μA	± (1,5 % of reading + 3 digits) 900 mV		rms max.
20 A 10 mA	± (2,5 % of reading + 5 digits) 900 mV		rms max.

7.5 Resistance ranges

Overload protection for resistance measurements: 600 V _rms .

Range	Resolution	Accuracy	Maximum test current	Max. open circuit voltage
200 Ω	0,1 Ω ± (0.8 % of reading + 4 digits)	2,5 mA 3,2 V
2 kΩ	1 Ω ± (0.8 % of reading + 2 digits)	200 μA 0,5 V
20 kΩ	10 Ω ± (0.8 % of reading + 2 digits)	40 μA 0,5 V
200 kΩ	100 Ω ± (0.8 % of reading + 2 digits)	4 μA 0,5 V
2 MΩ	1 kΩ ± (0.8 % of reading + 2 digits)	400 nA 0,5 V
20 MΩ	10 kΩ	± (2 % of reading + 5 digits)	40 nA	0,5 V

7.6 Diode and Continuity Testing

The accuracy indicated below is valid in the range of 0.4 V to 0.9 V.

Overload protection for diode testing: 600 V _rms .

The built-in buzzer sounds if the resistance R falls below 50 Ω.

Range	Resolution	Accuracy	Maximum test current	Max. open circuit voltage
→+ >>	1 mV	± (1.5 % of reading + 5 digits)	1,5 mA	3,2 V

7.7 Capacitance ranges

Conditions: Capacitors must be discharged before testing and then connected to the meter according to the indicated polarity.

Range	Resolution	Accuracy	Frequency
2 nF	1 pF	± (3.0 % of reading + 4 digits)	40 Hz
20 nF 10 pF	± (3.0 % of reading + 4 digits)		40 Hz
200 nF	100 pF ± (3.0 % of reading + 4 digits)		40 Hz
2 μF	1 nF	± (3.0 % of reading + 4 digits)	40 Hz
20 μF	10 nF	± (3.0 % of reading + 4 digits)	40 Hz
200 μF	100 nF ± (3.0 % of reading + 4 digits)		40 Hz

7.8 Frequency ranges

The frequency to be measured must have a minimum input signal of 200 mV_rms .

Range	Resolution	Accuracy for 5 Vrms max.	Minimum input frequency	Overload protection
2 kHz	1 Hz	± (1.5 % of reading + 5 digits)	20 Hz	600 Vrms
20 kHz	10 Hz	± (1.5 % of reading + 5 digits)	200 Hz	600 Vrms
200 kHz	100 Hz	± (1.5 % of reading + 5 digits)	2 kHz	600 Vrms

8. Measuring with BENNING MM 3

8.1 Measurement preparation

The BENNING MM 3 must be used and stored only at the indicated storage and working temperatures, avoid exposure to continuous sunlight.

• Check the rated voltage and current indications on the test leads. The safety test leads provided with the BENNING MM 3 correspond specifically to the rated voltage and current of the BENNING MM 3.
• Inspect the test leads for damaged insulation. If the insulation is damaged, the test leads should be discarded immediately.
• Check test lead continuity. If the conductor in the test lead is damaged, the leads should be discarded immediately.
• Remove test leads from circuit to be measured before turning the rotary switch ⑤ to select another function.
• If the BENNING MM 3 is used near strong noise generating sources, the display may become unstable and measurement errors may arise.

8.2 Voltage and current measurement

To avoid electrical shock, observe the maximum rated voltage to earth ground!

The maximum rated voltage that should be applied between any of the following terminals of the BENNING MM 3 and earth ground is 600V .

• COM terminal 8
• Input terminal for V, Ω, and Hz ⑦
• Input terminal for μA/ mA range ⑨
• Input terminal for 20 A range ⑧

Electrical hazard! Maximum permissible circuit voltage for current measurement is 500 V! If a safety fuse blows at a voltage above 500 V the BENNING MM 3 could be damaged. A damaged tester presents an electrical shock hazard to the user!

8.2.1 Voltage measurement

• Select the appropriate range with the rotary switch ⑤ of the BENNING MM 3.
• Use the selector switch ④ of the BENNING MM 3 to select the required direct (DC) or alternating (AC) voltage to be measured.
• Connect the black safety test lead to the COM-terminal 8 of the BENNING MM 3.
• Connect the red safety test lead to the input terminal for V, Ω, and Hz ⑦ of the BENNING MM 3.
• Connect the safety test leads to the circuit measurement points and read the measured value on the digital display ① of the BENNING MM 3.

see Figure 2: Direct voltage measurement

see Figure 3: Alternating voltage measurement

8.2.2 Current measurement

• Select the appropriate range with the rotary switch ⑤ of the BENNING MM 3.
• Use the selector switch ④ of the BENNING MM 3 to select the required direct (DC) or alternating (AC) current to be measured.
• Connect the black safety test lead to the COM-terminal 8 of the BENNING MM 3.
• Connect the red safety test lead to the input terminal for the A/ mA range ⑨ for currents up to 200 mA, or to the input terminal for the 20 A range ⑩ for currents between 200 mA and 20 A of the BENNING MM 3.
• Connect the safety test leads to the circuit measurement points and read the measured value on the digital display ① of the BENNING MM 3.

see Figure 4: DC current measurement

see Figure 5: AC current measurement

8.3 Resistance Measurement

• Select the appropriate range with the rotary switch ⑤ of the BENNING MM 3.
• Connect the black safety test lead to the COM-terminal 8 of the BENNING MM 3.
• Connect the red safety test lead to the input terminal for V, Ω, and Hz ⑦ of the BENNING MM 3.
• Connect the safety test leads to the circuit measurement points and read the measured value on the digital display ① of the BENNING MM 3.

see Figure 6: Resistance measurement

8.4 Diode Testing

• Turn the rotary switch 5 of the BENNING MM 3 to select the appropriate range identified by a buzzer and diode symbol (▶, ▶)
• Connect the black safety test lead to the COM-terminal 8 of the BENNING MM 3.
• Connect the red safety test lead to the input terminal for V, Ω, and Hz ⑦ of the BENNING MM 3.
• Connect the safety test leads across the diodes and read the measured value on the digital display ① of the BENNING MM 3.
• For a typical silicone diode tested in the forward-biased direction a voltage flow between 0,500 V and 0,900 V is displayed. A display showing "000" indicates a short circuit in the diode, whereas a display showing "1" indicates an open circuit in the diode.
• For a diode tested in the reverse-biased direction the display reads "1". If the diode is damaged, the display will show "000" or other values.

see Figure 7: Diode Testing

8.5 Continuity Testing with Buzzer

• Turn the rotary switch ⑤ of the BENNING MM 3 to select the appropriate range identified by a buzzer and diode symbol (▶).
• Connect the black safety test lead to the COM-terminal ⑧ of the BENNING MM 3.
• Connect the red safety test lead to the input terminal for V, Ω, and Hz ⑦ of the BENNING MM 3.
• Connect the safety test leads to the circuit to be measured. If the circuit resistance between the COM-terminal ⑧ and the input terminal for V, Ω and Hz ⑦ falls below 50 Ω, then the built-in buzzer in the BENNING MM 3 emits a continuous tone.

see Figure 8: Continuity Testing with buzzer

8.6 Capacitance Measurement

CAUTION! Capacitors must be completely discharged before attempting capacitance measurement! Never apply voltage to the input terminals for a capacitance measurement as this could destroy or damage the tester! A damaged tester may present an electrical shock hazard to the user!

• Use the rotary switch ⑤ to select the appropriate range on the BENNING MM 3.
• Establish the polarity of the capacitor and discharge the capacitor completely.
• Connect the fully discharged capacitor according to its polarity to the input terminals for capacitance measurement ⑥ of the BENNING MM 3 and read the measurement value on the digital display ① of the BENNING MM 3.

see Figure 9: Capacity Testing

8.7 Frequency measurement

• Use the rotary switch 5 to select the appropriate range on the BENNING MM 3.
• Connect the black safety test lead to the COM-terminal ⑧ of the BENNING MM 3.
• Connect the red safety test lead to the input terminal for V, Ω, and Hz ⑦ of the BENNING MM 3. Observe the voltage range of the BENNING MM 3 for frequency measurements!
• Connect the safety test leads to the circuit measurement points and read the measured value on the digital display ① of the BENNING MM 3.

see Figure 10: Frequency measurement

9. Maintenance

Remove test leads and turn the power off before opening the BENNING MM 3! Dangerous voltage!

Any work to be carried out on an opened BENNING MM 3 under voltage is strictly reserved for qualified electrotechnical personnel who must take special precautionary measures to avoid accidents.

This is how to ensure that the BENNING MM 3 is free from any voltage before the instrument is opened:

• first remove the safety test leads from measured object.
• then remove both safety test leads from the BENNING MM 3.
• turn the rotary switch ⑤ to the "OFF" position.

9.1 Instrument safe-guarding

In certain circumstances, safety during the use of the BENNING MM 3 can no longer be guaranteed; when for instance:

- there is visible damage to the housing

- measurement errors occur

- the instrument has been subjected to prolonged storage under unfavorable conditions and

- the instrument has been subjected to severe transport stresses.

In such cases the BENNING MM 3 must be immediately switched off, removed from the measurement points and secured against any future unintentional operation.

9.2 Cleaning

Wipe the case of the BENNING MM 3 with a clean dry cloth (exception: special cleaning cloths). Do not use any solvents and/or abrasives to clean the BENNING MM 3.

9.3 Battery replacement

Remove test leads and turn the power off before opening the BENNING MM 3! Dangerous voltage!

The BENNING MM 3 is powered by a 9 V block battery. Battery replacement (see figure 11 below) becomes necessary when the low battery indicator shows in the display ③.

This is how to change the battery:

• Remove the safety test leads from the measured circuit.
• Remove the safety test leads from the BENNING MM 3.

- Turn the rotary switch ⑤ to the "OFF" position.

- Remove the protective rubber holster ⑪ from the BENNING MM 3.

- Place the BENNING MM 3 on its front side and remove the three screws from the case back.

- Lift the end of the case back near the input terminals until it gently unsnaps from the case front at the end nearest to the LCD display ①.

- Remove the empty battery from inside the case front and carefully disconnect it from the battery connector leads.

- Snap the battery connector leads to the terminals of a new battery and reinsert the battery into the case front. Ensure that the battery leads do not become pinched between the case back and case front.

- Press the case back and case front together again and reinstall the three screws.

- Place the BENNING MM 3 back into its protective rubber holster ⑪.

see Figure 11: Battery replacement

Please contribute to environmental protection! Batteries should not be thrown into domestic refuse bins! They can be discarded at collection points for old batteries or special refuse. Please contact your municipality for more information.

9.4 Fuse replacement

Remove test leads and turn the power off before opening the BENNING MM 3! Dangerous voltage!

The BENNING MM 3 is protected from overloading by a built-in 1 A (G-cartridge) fast blow fuse and a built-in 16 A (G-cartridge) fast blow fuse (see figure 12).

This is how to replace the fuses:

• Remove the safety test leads from the measured circuit.
• Remove the safety test leads from the BENNING MM 3.
• Turn the rotary switch ⑤ to the "OFF" position.
• Remove the protective rubber holster ⑪ from the BENNING MM 3.
• Place the BENNING MM 3 on its front side and remove the three screws from the case back.
• Lift the end of the case back near the input terminals until it gently unsnaps from the case front at the end nearest to the LCD display ①.

Do not remove any screws from the printed circuit board of the BENNING MM 3!

• Lift the printed circuit board from the front case.
• Gently pry one end of the defective fuse loose from the fuse holder.
• Then slide the defective fuse completely out of the fuse holder.
• Install a new fuse of the same rating, fast acting characteristic and size.
• Make sure the new fuse is centered in the fuse holder.
• Replace the printed circuit board into the case front.
• Ensure that the battery leads do not become pinched between the case back and case front.
• Press the case back and case front together again and reinstall the three screws.
• Place the BENNING MM 3 back into its protective rubber holster ⑪ again. see Figure 12: Fuse replacement

9.5 Calibration

Benning guarantees compliance with the technical and accuracy specifications stated in the operating manual for the first 12 months after the delivery date.

To maintain the specified accuracy of the measurement results, the instrument must be recalibrated at regular intervals by our factory service. We recommend a recalibration interval of one year. Send the appliance to the following address:

Fuse F 16 Å, 500 V, D = 6.35 mm, L = 32 mm, part no. 749770

Fuse F 1 A, 500 V, D = 6.35 mm, L = 32 mm, part no. 749669

10. How to use the protective rubber holster

• The safety test leads can be stored by wrapping them around the protective rubber holster ⑪ and then clipping the probes into the protective probe holders on the rear of the holster ⑪ (see figure 13).
• A safety test lead can be clipped into the probe holder on the protective rubber holster ⑪ with the test probe protruding, in order to apply the probe together with the BENNING MM 3 to a measuring point.
• The rear tilt stand on the protective rubber holster ⑪ allows the BENNING MM 3 to be placed standing upright (for easier display reading) or hung up (see figure 14).
• The protective rubber holster ⑪ can also be hung on a nail if so desired.
  see Figure 13: Winding up the safety test leads
  see Figure 14: Erecting the BENNING MM 3

11. Technical data of the measuring accessories

• Standard: EN 61010-031,
• Maximum rated voltage to earth ( ± ) and measuring category:
  With push-on caps: 1000 V CAT III, 600 V CAT IV,
  Without push-on caps: 1000 V CAT II,
• Maximum rated current: 10 A,
• Protective class II (回), continuous double or reinforced insulation,
• Contamination class: 2,
• Length: 1.4 m, AWG 18,

-Environmentalconditions:

Maximum barometric elevation for making measurements: 2000 m,

Temperatures: 0 °C to + 50 °C, humidity 50 % to 80 %

- Only use the measuring leads if in perfect and clean condition as well as according to this manual, since the protection provided could otherwise be impaired.

- Throw the measuring lead out if the insulation is damaged or if there is a break in the lead/ plug.

- Do not touch the bare contact tips of the measuring lead. Only grab the area appropriate for hands!

- Insert the angled terminals in the testing or measuring device.

12. Environmentalnote

At the end of the product's useful life, please dispose of the device at collection points provided in your community.

7.1 Plages de tensions continues