Gordon NCAT Calibration, the 1 thing you can do to save your NCAT

NCAT Calibration

A Gordon NCAT Calibration is one of the most reliable calibrations you can get for your lab. It’s not because we think we’re the best at them ( Although we probably are), but because we go above and beyond when it comes to doing our homework.

How the NCAT was made

The NCAT ignition furnace was built and developed in the early 2000s through a partnership between Barnstead Thermolyne and the National Center for Asphalt Technology. NCATs main goal was to develop a furnace that could separate AC from the aggregate automatically, without having to continuously pull out your basket, weigh it, and put it back in. This was the common method with the other models on the market.

Fortunately for us, their design worked and ultimately became the standard for measuring asphalt content.

How the furnace works

The NCAT ignition furnace works the same whether you have a 240-volt furnace or a 208-volt (Although we think you should reconsider that 208). You put your sample in, press a button, and when the furnace tells you it’s done, pull out your basket. For most people, this is all they think they need to know.

This is why they will struggle to produce a quality product.

The NCAT isn’t an intelligent unit. It can’t tell you when something is wrong unless it’s one of the 11 NCAT error codes. Your furnace relies on four main systems to work in tandem with each other in order to produce good results. They are the electronic balance, temperature control, lift, and internal power controls. These are the main components that we focus on in a Gordon NCAT Calibration.

Electronic Balance

You may or may not know this, but the NCAT Balance relies heavily on a proper calibration in order to function correctly. It is incredibly sensitive and the slightest movement or misplacement can alter your final results.

Most scale calibration companies don’t have to worry about the scales moving or how the weight is placed on the plate. They just put down the weight, measure the result, and move on (Insert caveman grunt here).

Imagine if your NCAT told you that you lost an extra 0.2 g, what would that do to your results?

Temperature Control

Obviously one of the key components in the loss-on-ignition method is heat. But how does the NCAT furnace manage that heat?

With Thermocouples

New Filter NCAT Thermocouple is something we focus on during Gordon NCAT Calibrations
Gordon NCAT Calibration, the 1 thing you can do to save your NCAT 4

When the end of a thermocouple gets hot, a tiny amount of voltage is created.

You can read about how thermocouples work here if you are interested

That voltage is then carried to the brains of the NCAT which calculates the temperature and then forwards that temperature to the heating system.

When you just do a scale calibration on an NCAT your thermocouples aren’t inspected for damage or wear. Nor is your logic system tested for inaccuracies. This can lead to improper heating which can ruin your test results.

Internal Power Controls

Your NCAT’s brain is finely tuned and therefore must receive the correct amount of voltage at all times. When the voltage is out of the range it needs, something strange happens to the logic.

Over the course of a few weeks, alarms start going off for no reason, calculations are corrupted, and eventually, safety systems can start to fail.

This is why when our Technicians perform a Gordon NCAT Calibration we focus on the internal power system to ensure that your NCAT’s brain doesn’t cause severe issues down the line.


Lift is one of the few systems that can tell you if there’s something wrong with your NCAT before there are any problems. When your lift is out of range your furnace cannot burn as efficiently or as effectively. This can lead to incorrect results and component failure.

How to test your lift

To test your lift, make sure that your furnace has been off, or is below 30°C. Turn the unit on and with the door closed, press the start button. Your display will show a negative number (Also known as your Highest Negative Value/HNV). This number can alert you to any possible issues.

A Gordon NCAT Calibration by Gordon Technical focuses heavily on these four systems as well as many underlying sub systems on your furnace. We have been servicing NCAT’s for over 15 years. In that time we have come across issues that many of you will (hopefully) never see. If you have any questions about service or would like find out more on a particular issue that you’re having, please send us an email to sales@gtssi.net or visit our website and ask for service there.

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