When Pass-Fail Isn’t Enough, Rely on MAC-TS4

Trust Magnetron Atmospheric Condition testing to evaluate the remaining life of the vacuum interrupters in your equipment.

Do You Know the Remaining Life of Your Vacuum Interrupters? 


The MAC-TS4 vacuum interrupter tester uses patented magnetron atmospheric condition (MAC) testing to determine the condition of vacuum interrupters in the field, shop, or laboratory.

Before the introduction of this vacuum interrupter test set, the accepted field service test for vacuum interrupters was a simple go/no-go test performed with an AC high potential test. Today, testing with our MAC test sets can prevent unnecessary damage to your circuit breakers and contactors by predicting the usable life of the vacuum interrupter.

Completely self-contained, the MAC-TS4 includes everything required to test your vacuum interrupters in the field, shop, or lab. It incorporates a high-voltage power supply, a back-lit LCD display, a built-in thermal printer, and is furnished with a complete set of test leads. A USB connection and the included Windows®-based software allow the technician to control operation of the MAC-TS4 with an external PC, download stored test results, and generate test reports, which simplifies reporting and asset management.

If you’re looking for a meaningful vacuum interrupter test, take a look at the outstanding capabilities of our new MAC-TS4 vacuum bottle tester, which can be used in the field, shop, or laboratory.

Want a demo? We can bring a demo of our test equipment directly to your doorstep. Our fleet is full of gear that lets you see firsthand how our products and services can keep your vacuum interrupters in service.

Benefits of MAC-TS4 Test Set

  • Quickly determine remaining useful life of vacuum interrupters

  • System parameters based on measurements of thousands of vacuum interrupters 

  • Easy to use graphical user interface
  • Stores up to 500 test results
  • Built-in thermal printer & computer interface
  • Lightweight and portable at 28.4 lbs (12.9 kg)

Vacuum Interrupter Testing Based on Penning Discharge Principle

Utilizing the Penning Discharge Principle, our MAC-TS4 vacuum interrupter test set can easily assess the pressure inside a vacuum interrupter. It can also determine wear and number of operations and predict the usable life of the vacuum interrupters used in your circuit breakers and contactors. Analysis is based on the same OEM leak-rate test performed at the factory. This type of testing could previously only be done at the assembly plant. 

Magnetic Field Test Coils Allow for Testing in the Field, Shop, or Lab

Our unique, patented, flexible magnetic field test coils are available for testing vacuum interrupters installed in switchgear and magnetic field coil test fixtures are available for testing when removed. The flexible magnetic field test coil is available in various lengths to accommodate most applications and is used in conjunction with the MAC-TS4 vacuum bottle interrupter tester. 

Rigid magnetic field test coils for the MAC-TS4 vacuum interrupter test set allows technicians to test vacuum interrupters in GE PowerVac breakers in place without disassembling. The Power/Vac rigid magnetic field test coil slides over the PowerVac pole assembly, allowing the technician to determine the interrupter’s remaining lifespan without removing the vacuum interrupter. The portable, rigid magnetic field test coil is the first of many breaker-specific coils developed by Vacuum Interrupters.

Magnetic field coil test fixtures are used in conjunction with the MAC-TS4 vacuum interrupter test set to test individual vacuum interrupters that have been removed from a circuit breaker or contactor. Magnetic field coil test fixtures are available in various sizes to accommodate most vacuum interrupters.

If you’ve already had a vacuum interrupter failure, we can provide a replacement vacuum interrupter for virtually any manufacturer’s medium voltage circuit breaker or contactor.

Contact us to discuss your requirements, or request additional information or a quotation on our vacuum interrupter testers, circuit breaker timers, or instrument transformer test set. 

Resources to Learn More About Testing

  • Predicting the Remaining Life of Vacuum Interrupters in the Field DOWNLOAD
  • Vacuum Interrupter Testing Using Magnetron Atmospheric Condition (MAC) Test Equipment DOWNLOAD

  • Product bulletin: MAC-TS4 Vacuum Interrupter Test Set DOWNLOAD
  • Vacuum Interrupters: Pressure vs Age DOWNLOAD

Knowledge Base

Keep up with the latest information from Vacuum Interrupters and developments from across the electrical industry.


If you have vacuum interrupter failure, need equipment testing, or would like to discuss your requirements, contact us for immediate assistance.

After Hours or Emergency Support Available 24/7 888.395.2021