Precision Zone Expertly Repairs Inverter-General Purpose Magnetek VCD703

Here at Precision Zone, one of our specialties is the repair services of general purpose inverter units. One series that we often work on is the VCD703 series, which is offered by Magnetek.

This series is offered in 200VAC or 400VAC input options, covering a wide range of different application. The 200V option has units available with outputs ranging from 0.7kW and going up to 55kW. The 400V option is slightly different, offering output ratings starting at 0.7kW and going up through 300kW!

This series has two basic modes of operations – speed control and torque control. If torque control is being used, an additional AI-14B card is required to allow an input torque reference signal. The digital operator located on the front panel also allows quick access to parameters for editing, fault codes if an alarm or fault happens to occur, as well as some monitoring functions of the drive for in-depth, current information regarding the way the unit is behaving.

When assessing the functionality of a Magnetek General-Purpose Inverter, our expert repair team of engineers and technicians conducts a four-step check:

    1. Visual Overview
    2. Static Test
    3. Checks Under Power
    4. Alarm Codes Verification

This overview is Precision Zone’s basic troubleshooting process. Once our repair team starts on the job, we use specialized and customized testing fixtures, Huntron trackers, signal generators, oscilloscopes, milli and megaohm meters, as well as any other necessary tools we have available to assure quality repair work. Most importantly, every repair is fully tested in our custom-built simulators under load with a motor to replicate real-life working environment.

Precision Zone goes as far as using heating chambers and overnight dynamic testing, when applicable, to guarantee performance of the repaired product when it arrives back with the customer.

Repair Process for General-Purpose Inverter Drives

Visual Overview

When conducting a visual check, the technician inspects the drive for any mechanical damage to the drive itself and any printed circuit boards (PCB). The technician then proceeds to verify connections are tight and correct inside the drive and there are no loose screws, wires or debris. Additionally, the unit is checked for any burn marks on the components, PCBs or chassis. During the visual inspection, excessive dirt on cooling components is noted as well as the functionality of the heat sink.

Basic Static Check

Input Module Testing

The input modules on these units can be tested by use of a digital multimeter with diode checking capabilities. Upon removing the cover, all of these terminals can be located along the terminal strip found within the unit.

Positive Lead Negative Lead Reading
R 'P' Terminal 0.42V-0.51V
S 'P' Terminal 0.42V-0.51V
T 'P' Terminal 0.42V-0.51V
'N' Terminal R 0.42V-0.51V
'N' Terminal S 0.42V-0.51V
'N' Terminal T 0.42V-0.51V

Output Module Testing

Using the same type of test as above, the output modules can be checked as well. Our technicians are also equipped with huntron devices further verify their integrity.

Positive Lead Negative Lead Reading
U 'P' Terminal 0.38V-0.54V
V 'P' Terminal 0.38V-0.54V
W 'P' Terminal 0.38V-0.54V
'N' Terminal U 0.38V-0.54V
'N' Terminal V 0.38V-0.54V
'N' Terminal W 0.38V-0.54V

Common Alarms for the Magnetek VCD703 General-Purpose Inverter Units

Alarm Code Description Checks
OC The output of the drive exceeds 120% of the rated current
  • Check cables for poor insulation
  • Perform magaohm test on motor
  • Use 'Output Module Testing' test to verify modules
  • Check for ground faults
EF# An external fault has been detected on terminal #*

*Number in alarm code denotes terminal with the fault

  • Verify external fault parameters
  • Verify external unit is closed if NC or open if NO
  • Swap out control card
CPF## CPF## alarms focus on a communication related issue on the drive control board
  • Check all connectors/plugs for secure connection
  • If comfortable, attempt to initialize and reload parameters
  • Replace drive

Full list of alarm troubleshooting, extracted from the manual:

This list of checks for certain alarms is primarily a good starting point and if any further troubleshooting or technical support is needed feel free to contact us via phone or email to get in touch with our experienced tech support team.

Learn the benefit of repairing your Magnetek General-Purpose Inverters with Precision Zone

  • Quick and Flexible Service
  • Fully Refurbished, not just repaired
  • Decades of Industry Experience
  • Superior Technology Knowledge and Support

Contact Us To Start Your Repair Today!

Recently Repaired Products

Magnetek VCD703-B005 image VCD703-B005 is an
Inverter-General Purpose manufactured by Magnetek
Discovered issues: Bad Capacitor(s), Bad Cooling Fans, Bad Orientation/Encoder Section/Board, Excessive Dirt/Debris, Leaky Capacitors (Open, Corroded Traces)
Drive Type: Magnetek AC Inverter
Series: 703
Input Voltage: 380/460V
Capacity: 3.7kW (5HP)

Magnetek VCD703-B015 image VCD703-B015 is an
Inverter-General Purpose manufactured by Magnetek
Discovered issues: Parameter/Setting Adjustment
Drive Type: Magnetek AC Inverter
Series: 703
Input Voltage: 380/460V
Capacity: 11kW (15HP)

Magnetek VCD703-B030 image VCD703-B030 is an
Inverter-General Purpose manufactured by Magnetek
Discovered issues: Bad Circuit Board Component(s), Bad Control Section/Board, Bad Gate Section/Board, Bad Power Section/Board, Leaky Capacitors (Open, Corroded Traces)
Drive Type: Magnetek AC Inverter
Series: 703
Input Voltage: 380/460V
Capacity: 22kW (30HP)