Major tech MT935 User manual

INSTRUCTION MANUAL
MOTOR & PHASE ROTATION INDICATOR
MT935

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Contents Page no
1. Introduction....................................................................................3
2. Symbols..........................................................................................3
3. Safety Information...........................................................................3
4. Accessories Included........................................................................4
5. Meter Description............................................................................4
6. Operation...................................................................................... 4
6.1. Determine Rotary Field Direction...............................................4
6.2. Non-Contact Rotary Field Indication...........................................5
6.3. Determine the Motor Connection...............................................6
6.4. Magnetic Field Direction...........................................................6
7. Battery Replacement........................................................................6
8. Specifications.................................................................................6
8.1. Determine Rotary Field Direction...............................................6
8.2. Non-Contact Rotary Field Indication...........................................7
8.3. Determine the Motor Connection...............................................7
8.4. Electrical Specifications............................................................7
8.5. Safety Specifications................................................................7
8.6. Environmental.........................................................................7
8.7. Mechanical Specifications.........................................................7

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1. INTRODUCTION
The MT935 is a handheld, battery-operated meter designed to detect the
rotary field of three-phase systems and determine motor-rotation direction.
2. SYMBOLS
The following symbols appear on the Meter or in this manual.
3. SAFETY INFORMATION
CAUTION identifies conditions & actions that may damage the meter.
WARNING identifies conditions & actions that pose hazard to the
user. To avoid possible electric shock or fire, do the following:
• Read the safety information carefully before using or servicing this meter.
• Adhere to local and national safety codes.
• Individual protective equipment must be used to prevent shock and
injury.
• Using this meter in a manner not specified by Major Tech may impair
safety features/protection provided by the equipment.
• Avoid working alone.
• Inspect the test leads for damaged insulation or exposed metal. Check
test lead continuity, damaged leads must be replaced, do not use the
meter if it appears to be damaged.
• Be careful when working above 30V AC RMS, 42V AC peak and 60V DC,
such voltages pose a shock hazard.
• When using the probes, keep fingers away from probe contacts, keep
fingers behind the finger guards on the probes.
• Measurements can be adversely affected by impedances of additional
operating circuits connected in parallel or by transient currents.
Risk of electric shock
Risk of Danger, Important information see manual.
Hazardous Voltage.
Equipment protected by double or reinforced insulation
Battery
Earth
AC or DC
Conforms to EU directives
Overvoltage (Installation) Category III. Pollution Degree 2 per
ICE 1010-1 refers to the level of Impulse withstand voltage
protection provided. Equipment of Overvoltage Category III is
equipment in fixed installations (e.g. electricity meter and
primary over-current protection equipment).

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• Verify operation prior to measuring hazardous voltages (voltages above
30V AC RMS, 42V AC peak and 60V DC).
• Do not use the meter with any of the parts removed.
• Do not use the meter around explosive gas, vapor, or dust.
• Do not use the meter in a wet environment.
4. Accessories Included
3 Piece Self-Retaining Test Leads, 3 Alligator Clips, 9V Battery & Manual.
5. METER DESCRIPTION
1 - Test Lead Input Jack
2 - L1 Indicator
3 - L2 Indicator
4 - L3 Indicator
5 - Clockwise Rotation Indicator
6 - Counter Clockwise Rotation Indicator
7 - ON/OFF Indicator
8 - ON/OFF Button
9 - Brief Instructions on
Instrument Rear
10 - Battery Cover
6. OPERATION
6.1. Determine Rotary Field Direction
1. Connect one end of the test leads to the Meter, make sure the L1, L2 and
L3 test leads are connected to the corresponding input jacks.
2. Connect the test probes to the three main phases, press the ON/OFF
Button, the green ON indicator shows that the meter is ready for testing.
3. Either the Clockwise or Counter Clockwise Rotary indicator illuminates
showing the Type of rotary field direction present.
4. The rotary indicator lights up even if the neutral conductor, N, is
connected instead of the Test lead input jacks.
5. Refer to Figure 1 (Shown on the back of the Meter) for more information.

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6.2. Non-Contact Rotary Field Indication
1. Disconnect all test leads from the Meter.
2. As shown in Figure 2, position the MT935 on the motor so that it is
parallel to the length of the motor shaft, the meter should be at least 1
inch away from the motor.
3. Press the ON/OFF Button, the green ON indicator shows that the
instrument is ready for testing.
4. Either the Clockwise or Counter Clockwise Rotary indicator illuminates
showing the type of rotary field direction present.
Note: The indicator will not operate with engines controlled by frequency
converters. The bottom of the Meter should be oriented towards
the drive shaft. See the Orientation Symbol on the Meter.
See Table for the minimum motor diameter and number of pole pair to
obtain a reliable test result.
Number of Rotary Number of Rotary Angle Between Min. Ø of
Pole Pair Field (1/min)at Frequency (Hz) Poles Motorcase
16 2/3 50 60 ˚ cm
1 1000 3000 3600 60 5.3
2 500 1500 1800 30 10.7
3 333 1000 1200 20 16.0
4 250 750 900 15 21.4
5 200 600 720 12 26.7
6 167 500 600 10 32.1
8 125 375 450 7.5 42.8
10 100 300 360 6 53.5
12 83 250 300 5 64.2
16 62 188 225 3.75 85.6
Figure 1 Figure 2

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6.3. Determine the Motor Connection
1. Connect one end of the test leads to the Meter, make sure the L1, L2
and L3 test leads are connected to the corresponding jack.
2. Connect the alligator clamps to the other end of the test leads.
3. Connect the alligator clamps to the motor connections, L1 to U, L2 to V,
L3 to W.
4. Press the ON/OFF Button, the green ON indicator shows that the
instrument is ready for testing.
5. Turn the motor shaft half a revolution towards the right.
Note: The bottom of the Meter should be oriented towards the drive
shaft. See the Orientation Symbol on the Meter.
Note: Either the Clockwise or Counter Clockwise Rotary indicator
illuminates showing the type of rotary field direction present.
6.4. Magnetic Field Detection
• To detect a magnetic field, place the Motor and Phase Rotation
indicator to a solenoid valve.
• A magnetic field is present if either the Clockwise or the Counter
Clockwise Rotary indicator illuminate.
7. BATTERY REPLACEMENT
This Meter uses a 9V battery. To replace the battery, follow these steps.
1. Place the LCD side of the Meter down on a non-abrasive surface.
2. With a screwdriver, loosen the screw of the battery compartment and
remove the lid. Remove the old batteries.
3. Insert the new batteries while observing the battery polarity shown in
the battery compartment.
4. Secure the battery compartment lid back in position with the screw.
Note: The Meter contains alkaline batteries. Do not dispose of these
batteries with other solid waste. Used batteries should be disposed
of by a qualified recycle or hazardous materials handler.
Nominal Voltage Rotary Direction 1 to 400V AC
Nominal Voltage Phase Indirection 120 to 400V AC
Frequency Range (fn) 2 to 400Hz
Test Current (In per phase) Less than 3.5mA
8. SPECIFICATIONS
8.1. Determine Rotary Field Direction
Function Range

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Frequency Range (fn) 2 to 400Hz
8.2. Non-Contact Rotary Field Indication
Function Range
Nominal Test Voltage (U me) 1 to 400V AC
Nominal Test Current (In per phase) Less than 3.5mA
Frequency Range (fn) 2 to 400Hz
8.3. Determine the Motor Connection
Function Range
Battery 9V alkaline, IEC 6LR61
Current Consumption Max 20mA
Battery life Minimum 1 year for average use
8.4. Electrical Specifications
Function Range
Electrical Safety Meets DIN VDE 0411,IEC 61010
DIN, VDE 0413-7, IEC 61557-7/EN
61557-7
Maximum Operating Voltage (Ume) 400V AC for all ranges
Protection Levels CAT III 1000V and CAT IV 600V
8.5. Safety Specifications
Function Range
Operating Temperature 0°C to 40°C
Operating Humidity 15% to 80%RH
Operating Altitude 2000m
Pollution Degree 2
Type of Protection IP40
8.6. Environmental
Function Range
Size (HxWxD) 135x75x31mm
Weight (With the battery) 174g
8.7. Mechanical Specifications
Function Range

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South Africa Australia