In high or medium voltage systems, relays are the most widely used devices. Their main purpose is to isolate a faulty section within just a few cycles while ensuring minimum interruption to the healthy sections. An ideal relay is a unit that acts while anticipating the damage of the faulty section. Relay connections become contaminated with use, or deteriorate with carbon particles, etc. Therefore, it is advisable for the manufacturer and also for the end user to check the behaviour of the relay after certain time intervals.
Over time, relay technology has evolved, and so has relay testing. A good number of test systems supported by the most recent microprocessor relays have been developed. When it comes to the smallest, lightest and most unrivalled relay test equipment, Amperis provides the best tools you need to test your protective relays and meters. The equipment is capable of coping with all the types of tasks that were previously carried out by large equipment.
Today's protective relays offer multiple protection functions that require a new level of refined test software and hardware, able to fully analyse the operation of the unit in "real life". Relay testing and each one of its facets can be easily handled with advanced relay test equipment. Previously, relay test sets were associated with something heavy and bulky. Under that condition, moving them to the field turned out to be a task only possible for a very strong man. But nowadays, with technological progress, relay test sets are smaller in size and easy to operate.
With the complete and sophisticated line of Amperis relay test equipment, each and every phase of relay testing can be handled effectively. In that sense, Amperis offers the powerful range of relay test sets that can live up to its reputation as a colossus. Amperis relay test equipment includes:
- AK-6 Three-Phase Relay Test Set
- AK-30 Three-Phase Relay Test Set
- AK-10 Three-Phase Relay Test Set
- APCI-600 Primary Current Injection Source
- ARFD 200 Test Set
- AMCCB250 Moulded Case Circuit Breaker Test Set
Purpose of Relay Testing:
Relays are discrete devices, unlike integrated circuits; they are used to provide a low-power logic signal to control a much larger power circuit. The relay helps to isolate the high voltage circuit from the low voltage logic circuit in order to protect the low power circuit. To achieve this, the relay has a small electromagnetic coil to control the logic circuit, and when the coil is energised it results in a magnetised switch with a high power rating that activates the high power circuit.
The relay that supplies a high amount of current to the headlights of a car is an example of this. Through the control of the relay, the low voltage logic circuitry from the car dashboard switches on the headlights.
Relay Test Equipment:
A relay generally has a coil, a set of contacts and a pole. There are two types of contacts in relay testing: normally open and normally closed. The normally open ones (N/O) are the set of contacts that are open when the relay is not activated, and normally closed (N/C) are the set of contacts that close when the relay is not activated.
Using relay test equipment requires appropriate knowledge. The equipment requires an understanding of its use. There are many new products for relay testing, each one accompanied by its user manual to help understand how it works.
Modern relay test sets generally incorporate features such as:
- Linear amplifiers with switched mode or feedback,
- Protection for open channels, overheating, short-circuited voltage channels, and internal faults.
- They are designed with an intelligent control system that realistically simulates the power system.
To avoid damage and to get better performance from relay test instruments, it is essential to know the basics of the equipment before using it:
- Make sure you store and transport your test set correctly.
- Do not try to force 1800 watts through a 14 awg 100' extension cord or an undersized bench wiring.
- Beware of condensation conditions.
- Take proper care of the ventilation openings, do not allow foreign material to get into the test set.
- Never try to connect a current amplifier to an external voltage source such as a battery or any other source.
- Do not try to trip the circuit breaker, drive a closing coil or connect any significant load with the contact output.