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TSW-155 Tri-State Instrument Laboratory Description:
Rotation of electrical motor shafts in the wrong direction can cause severe mechanical damage to expensive machinery. A motor rotation indicator can quickly show this shaft rotation direction in advance, therefore becoming a valuable piece of test equipment.

On a three phase motor, direction of the shaft rotation is determined by the three phase rotation of supply line voltage and the corresponding connections to the motor. When the ABC phases of the line voltage are connected to the ABC phases of the motor it will rotate in a clockwise direction. If the ABC phases of the line voltage are connected to the CBA phases of the motor it will rotate in a counterclockwise direction.

The TSW-155 Motor Rotation Indicator provides a positive indication of direction of shaft rotation in unmarked multi-phase motors and can identify phasing of transformer windings. It is small, light weight, can be carried easily and is built to last. With push button operation and instant readings.

  1. Connect Leads
    Disconnect motor from line, connect the three indicator leads to the three motor leads.
  2. Push Button
    Push the “ON” button and hold it down. Rotate the motors shaft by hand, 1,4 turn in desired direction. Note first direction, ABC or CBA and release button.
  3. Set Rotation
    If ABC showed on meter then connect phase ABC of three phase line to motor leads identified ABC by the indicator leads. The motor will turn as desired. If CBA showed on the meter reverse leads A and C and repeat steps two and three.


  • Size - 4” X 2 7/8 X 1 9/16
  • Leads: 30” long, terminated in insulated alligator dips.
  • Weight: 1 Lb. Battery: 1”C”


TSW-22 Tri-State Instrument Laboratory Description:
The Model TSW-23 Voltage Divider is a 10:1 voltage divider for use on AC or DC circuits up to 5000 Volts. It is a self contained unit designed to be used in conjunction with “Fluke” brand digital multimeter models 70, 73, 75, 77, 79, 21, 23, 25, 27, 29, 83, 85, 87, 8060A, and 8062A. Extending the voltage ranges by a factor of 10 up to 5000 Volts AC or DC. The unit plugs directly into the common and volts input jacks of the digital multimeter via banana plugs on the box. Two leads come out of the box and are terminated at their ends with 15KV rated probes and booted screw-on alligator clips. The probes and boots are color coded, red and black, and the same polarity should be observed each time the divider is used


  • Accuracy - (+1-) 1.5% FS
  • The box is thermosetting black phenolic measuring 4” X 2 7/8 X 1 9/16
  • Leads - 36” in length with insulation rated at 10KV.
  • Probes: Mueller 27 , 20 AMP. Clamp /Stainless Steel w/Insulating Rubber Boot 


TSW-45 Tri-State Instrument Laboratory Description:
The Model TSW-45 Phase Sequence Indicator provides positive phase sequence indications, instant readings. It’s compact, rugged and reliably designed with no moving parts, batteries or binding posts.

Connect leads
Connect three leads across a 3-phase 600 to 4160 volt, 50/60 Hz circuit in any sequence.

Read phase sequence
The ABC or CBA will glow showing phase sequence.

Detect open phase
The (A) RED, (B) WHITE, or (C) BLUE phase lamp glows to indicate an open phase, open test lead or no contact of test clip.

A three phase alternator generates three sine wave voltage differing in phase by 120 electrical degrees. The order in which the three voltages succeed one another is called phase sequence or phase rotation, determined by the direction of rotation of the alternator. The three output lines carrying these phased voltages are usually identified by the letters A, B, and C, so that the clock wise rotation sequence is ABC, and the counter-clock wise rotation sequence is CBA. Inter-changing any two of the phase lines will, of course, reverse the phase sequence. The phase sequence indicator permits the operator to quickly determine the phase sequence in order to properly install motors or other equipment, or to make changes in the wiring.


  • Size: 6 3/4” X 4 3/4” X 2 1/8”
  • Leads: 36”, color coded, and terminated in insulated clips. Weight: 1 lb.
  • Carrying case: Included


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