Vector Drive - How it Works and Troubleshooting Guide

Applies to machines built from: 
January, 2007

How it Works

The Haas Vector drive is the source of power for the spindle motor and the servo amplifiers. There are three sizes of Haas Vector drives: 20HP [1], 40HP [2] and 60HP [3].

The vector drive consists of these three internal sections:

High-Voltage Power Supply: Supplies a nominal 335 VDC to both the vector drive and to all of the axes servo amplifiers.

Amplifier: Operates exactly like the servo amplifiers, but it is capable of much higher current. It operates from analog signals sent by the Maincon or MOCON. These signals represent the vector current commands that control the torque, velocity, and direction.

Regeneration Load: Ensures that the energy produced by the deceleration of the motors does not cause an over-voltage condition, but instead is absorbed by the load resistors.

The vector drive also supplies three additional signals: an analog measurement of the high voltage DC Bus, a power supply fault signal to the I/O PCB, and a fault signal from the amplifier section to the Maincon/MOCON . It employs a true, closed-loop vector system to deliver peak performance and precise speed control under load.

Symptom Possible Causes Corrective Action Section

Alarm 123 SPINDLE DRIVE FAULT and Alarm 993 SHORT CIRCUIT

Alarm 2040 VECTOR DRIVE OR SPINDLE-AMPLIFIER SHORT CIRCUIT

The vector drive detected a short. Inspect the Delta-Wye contactor and measure the terminal resistance. 1

Alarm 123 SPINDLE DRIVE FAULT

Alarm 648 DC BUS SHORTED

Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT and Alarm 160 LOW INCOMING LINE VOLTAGE

There is a problem with the DC Bus. Compare the measured DC voltage to the Diagnostic page. 2

Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT and Alarm 647 REGEN LOAD SHORTED

There is a problem with the REGEN. Measure the resistance across the REGEN leads. 3

Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT and Alarm 200 HIGH VOLTAGE POWER SUPPLY OVER–TEMPERATURE

Alarm 2038 VECTOR DRIVE OR SPINDLE AMPLIFIER–OVER TEMPERATURE

There is a problem with the vector drive cooling fan. Inspect the cooling fan. 4

Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT and Alarm 444 REGEN REMAINED ON TOO LONG

There is a problem with the incoming AC power. Measure the incoming voltage to the machine. 5
The Machine Fails to Maintain Spindle Orientation. The vector drive output is unbalanced. Measure voltage outputs across the vector drive terminals. 6

Section 1

Symptom: Alarm 123 SPINDLE DRIVE FAULT and Alarm 993 SHORT CIRCUIT, or Alarm 2040 VECTOR DRIVE OR SPINDLE-AMPLIFIER SHORT CIRCUIT

Possible Cause: The vector drive detected a short.

Corrective Action:

Inspect the Wye-Delta assembly. Make sure that all connections are tight, and that there are no signs of arching or burn marks on the contactors, the jumper bus-bar or on the contacts. Press POWER ON. Make sure that only the Wye contactor is energized when no spindle speed is commanded. If both contactors are closed at the same time, one of the contactors may be stuck (welded shut). The vector drive sees this condition as a short.

Inspect the vector drive. Press POWER OFF. If the vector drive voltage indicator light is on, do not touch the electrical components. The high voltage in the control cabinet can kill you. Wait for the voltage indicator LED on the vector drive to go off completely. Disconnect terminals 2 and 3 and check for a short to the spindle motor circuit by measuring the resistance of terminal 2 to 9, 10, and 11. Measure terminal 3 to 9, 10, and 11.

If you detect a short:, remove the motor cables at vector drive terminals 9, 10, and 11. Press POWER ON. Release the EMERGENCY STOP to enable the servos. Press RESET. If the alarm goes away, there is a problem with the spindle motor and not the vector drive.

Inspect the spindle motor cables. Make sure the spindle motor cables are not contaminated or pinched.

Section 2

Symptom: Alarm 123 SPINDLE DRIVE FAULT, Alarm 648 DC BUS SHORTED, Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT, and Alarm 160 LOW INCOMING LINE VOLTAGE

Possible Cause: There is a problem with the DC Bus.

Corrective Action:

Press POWER ON. Measure the DC voltage between terminals 2 and 3 on the vector drive. Compare the measured voltage with the DC VOLTAGE on the diagnostics page on the control. The readings must match +-2%.

If the readings do not match, the problem can be:

  • A bad connection on the 640C cable. Make sure there is a tight connection on the J3 connector on the Vector Drive and the P17 connector on the Maincon/Mocon.
  • A faulty Vector Drive if you have incorrect voltage at P17.
  • A faulty Maincon/Mocon if you have the correct voltage on the 640C cable at the P17 connector of the Maincon/Mocon. There is 0.01 VDC for every 1 VDC Buss. For example, 320 VDC must show 3.2VDC.

Disconnect the DC Bus cables from terminals 2 and 3 on the vector drive. Power on the machine. Monitor the DC VOLTAGE on the diagnostics page of the control.

  • If the DC Bus goes back to the nominal value, there is a short in one of the servo amplifiers. A low resistance or a short is a sign of a faulty servo amplifier.
  • If the readings match and the alarm continues, the problem is a faulty vector drive.

Section 3

Symptom: Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT, and Alarm 647 REGEN LOAD SHORTED

Possible Cause: There is a problem with the REGEN.

Corrective Action:

Press POWER OFF. If the vector drive voltage indicator light is on, do not touch the electrical components. The high voltage in the control cabinet can kill you. Wait for the voltage indicator LED on the vector drive to go off completely.

Disconnect the REGEN load leads from the vector drive at terminals 1 and 2. Measure the resistance across the leads. The reading must be as follows:

  • 2-resistor box: between 9.5 and 12.5 ohms.
  • 3-resistor box: between 6.3 and 8.3 ohms ohms. (As shown in the illustration.)
  • 4-resistor box: between 4.6 and 6.6 ohms.

If the REGEN loads are within specification, there can be a problem with the vector drive. Measure the resistance across terminals 1 and 3 on the vector drive. A short is a sign of a faulty vector drive.

Section 4

Symptom: Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT and Alarm 200 HIGH VOLTAGE POWER SUPPLY OVER–TEMPERATURE, or Alarm 2038 VECTOR DRIVE OR SPINDLE AMPLIFIER–OVER TEMPERATURE

Possible Cause: There is a problem with the vector drive cooling fan.

Corrective Action:

An over-temperature alarm is generated when the vector drive's heat-sink reaches 90°C. The cooling fan must turn ON when the heat-sink temperature reaches 50°C. The cooling fan must turn OFF as the heat-sink cools down. Measure the temperature of the vector drive's heat-sink through the exhaust vents when this alarm occurs. If the temperature is above 60°C and the fan is not ON, the vector drive has a faulty cooling fan. Replace the cooling fan.

Section 5

Symptom: Alarm 292 HIGH VOLTAGE POWER SUPPLY FAULT and Alarm 444 REGEN REMAINED ON TOO LONG

Possible Cause: There is a problem with the incoming AC power.

Corrective Action:

Measure the incoming voltage to the machine. Make sure that the incoming voltage is within the range of the transformer’s tap [1]. Move the lines to the correct tap if needed.

Section 6

Symptom: The Machine Fails to Maintain Spindle Orientation.

Possible Cause: The vector drive output is unbalanced.

Corrective Action: Disconnect the motor cables at the vector drive. Push POWER ON. Push RESET to clear any alarms. Use a multimeter to measure the DC voltage across the following terminals on the vector drive (see the illustration):

3 and 9

3 and 10

3 and 11

The voltage must be 160-175VDC in all three readings. If any of the voltage readings is 0V or 330V, then this is a sign of an unbalanced output from the vector drive.

Be aware: Many service and repair procedures should be done only by authorized personnel. The service technicians at your Haas Factory Outlet (HFO) have the training, experience, and are certified to do these tasks safely and correctly. You should not do machine repair or service procedures unless you are qualified and knowledgeable about the processes.

Danger: Some service procedures can be dangerous or life-threatening. DO NOT attempt a procedure that you do not completely understand. Contact your Haas Factory Outlet (HFO) and schedule a service technician visit if you have any doubts about doing a procedure.

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