Comparators are the sensitive electronic measuring instruments that provide sub micron measurements that you cannot measure with standard mechanical instruments of measurements. Some sectors that use comparators for precise measurements are the aerospace, marine, industrial and metrology sectors.

Comparators are available in different types depending on the measurement requirements. For example, a digital voltage comparator compares the input voltage to a reference voltage and is available in the form of various kinds of integrated circuits. An optical comparator on the other hand is an instrument that projects a magnified image onto a screen for comparing the image with a standard scale used to measure or examine parts. Depending on your needs, you can also buy other types of comparators. Some examples are comparator amplifier, dual comparator and differential comparator.

Some important parameters you must consider before you buy a comparator are

1. The various types of comparators available
2. The level of precise measurements you require
3. The type of measurements you require
4. The capabilities of each comparator

Action Steps
The best contacts and resources to help you get it done

Buy comparators from a reliable comparator manufacturer

Once you understand your requirements, approach a specific manufacturer to buy the comparators.

I recommend: Maxim Integrated Products is a manufacturer of different types of voltage comparators like a general-purpose low voltage comparator, a high-speed comparator and amplifier. S-T Industries is a manufacturer of horizontal optical comparators and vertical optical comparators. You can buy a diaphragm analog comparator from Air Logic, another reputable manufacturer.

Buy a comparator from a comparator distributor or retailer

You can compare different comparators based on the prices and features at distributors or retailers' websites.

I recommend: General Tool & Supply Co. is a distributor from whom you can buy hand held comparators. You can buy an analog comparator from MSC Industrial Direct, a distributor of various types of comparators and accessories. Newark is a distributor that sells a range of voltage comparator chips.

Buy a used comparator

For a cost-effective solution, try buying a certified used comparator.

I recommend: You can also buy used comparators from Used-Line.com, a reputable retailer of used testing and measurement devices. Unlimited Services is a comparators supplier from whom you can buy a recertified old, calibrated and used optical comparator. Inspec is another distributor that sells pre-owned used optical comparator.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Take proper care while handling the comparators, as they are very sensitive to variations in temperature, dust and surrounding conditions.
• •  Get the comparators serviced and calibrated as per the manufacturer's guidelines so that the measurements are accurate.