Confident Switching: Unveiling The Features of UC3 Latching Relays for IEC62055-31 Compliance

In the world of electrical switching, UC3 Latching Relays designed for IEC62055-31 compliance stand out as reliable and efficient components. This article aims to unravel the features of UC3 latching relays, focusing on their adherence to IEC62055-31 standards, short-circuit current carrying capacity, and fault current making capacity. Gain insights into these features to switch with confidence in various electrical applications.

The Essence of UC3 Latching Relays

UC3 Latching Relays are engineered for precision switching applications, offering a reliable solution for scenarios where compliance with IEC62055-31 standards is crucial. This section introduces the fundamental characteristics that make UC3 relays stand out in the realm of latching relays.

IEC62055-31 Compliance in Latching Relays

A. Adherence to Standards: UC3 Latching Relays are meticulously designed to comply with IEC62055-31 standards, ensuring seamless integration into systems that require precision and reliability in switching mechanisms.

B. Compatibility with Metering Systems: These relays are tailored for metering applications, providing a secure and compliant solution for accurate data collection and measurement processes.

Annex C (normative) Performance requirements for payment meters with load switching utilisation categories UC2, UC3 and UC4

C.3 Electrical endurance

The test shall be carried out on a new sample under the following conditions:

1.payment meter in normal operating condition;

2.room temperature at reference conditions;

3.1 m length cable with current carrying capacity of Ic;

4.supply voltage at Uc;

5. load current at Ic and PF = 1,0;

6.number of operating cycles equal to 5 000, with 10 s make time and 20 s break time.

7. Repeat the test using the same sample, but with the following changes:

load current at Ic and PF = 0,5 inductive

C.5 Fault current making capacity

The payment meter shall be capable of making into simulated fault currents as given in this Clause. Perform the test on a new payment meter sample under the following conditions:

1.climatic conditions at reference values;

2.payment meter in the normal operating condition;

3.voltage source at Uc;

4.3 pre-fusing operating cycles at Ic and PF = 1,0 at 10 s intervals;

5. prospective test current at 2,5 kA r.m.s. for utilisation category UC2;

6.prospective test current at 3 kA r.m.s. for utilisation category UC3;

7.prospective test current at 4,5 kA r.m.s. for utilisation category UC4;

8.power factor of test current shall be inductive in accordance with Table 16 of IEC 61008-1;

9.frequency at reference value;

10.current tolerance +5 % –0 %;

11.voltage tolerance +5 % –5 %;

12.power factor tolerance +0,00 –0,05.

NOTE 1 One pre-fusing operating cycle is to maintain the switch contacts in the closed condition for 5 s, then to maintain the switch contacts in the open condition for 5 s. Cause the payment meter to close the load switch contacts into the above prospective test current and to remain in the closed position. The test current shall be maintained to flow up to the first zero point crossing of the current, at which point, the test equipment shall disconnect the voltage source. Repeat the test 3 times on the same sample with a minimum delay of 1 min between each test. Plot a graph of the voltage and the test current waveform during each test and verify that the test was executed as is required.

C.6 Short-circuit current carrying capacity

The payment meter shall withstand simulated short-circuit currents as may be experienced under short-circuit conditions in a payment meter installation. Test 1 shall be carried out on a new payment meter sample under the following conditions:

1. climatic conditions at reference values;

2.series connection of a voltage source, the payment meter under test, load to produce the required test current and a test switch;

3.payment meter in the normal operating condition;

4.3 pre-fusing operating cycles at Ic and PF =1,0 at 10 s intervals;

5. load switch contacts in the closed position; voltage source at Uc;

6.prospective test current at 4,5 kA r.m.s. for utilization category UC2;

7.prospective test current at 6 kA r.m.s. for utilization category UC3;

8.prospective test current at 10 kA r.m.s. for utilization category UC4;

9.power factor of test current shall be inductive in accordance with Table 16 of IEC 61008-1;

10.test switch closing at zero voltage crossover;

11. test switch opening at the first subsequent zero voltage crossover, thus remaining in the closed position for one half cycle of the supply voltage;

12.frequency at reference value;

13. current tolerance +5 % –0 %;

14.voltage tolerance +5 % –5 %;

15.power factor tolerance +0,00 –0,05.

Repeat the test 3 times on the same sample with an interval of at least 1 min between each test. Plot a graph of the voltage and the test current waveform during each test and verify that the test was executed as is required.

During and after the test the following requirements shall be met:

1. it is permissible that the contacts may weld or burn away;

2.the surroundings of the payment meter shall not be endangered;

3.protection against indirect contact shall remain assured; Test 2 shall be carried out on a new sample under the following conditions:

4. the same conditions as for Test 1 shall apply, except that the prospective test current shall be 2,5 kA r.m.s. for utilisation category UC2, 3 kA r.m.s. for utilisation category UC3 and 4,5 kA r.m.s. for utilisation category UC

Applications in Various Industries

A. Metering and Billing Systems: UC3 Latching Relays find extensive use in metering and billing systems, where compliance with IEC standards and reliable switching are critical for accurate data collection.

B. Industrial Automation: In industrial settings, UC3 relays provide a trustworthy solution for precise switching, contributing to the efficiency and safety of automated processes.

C. Power Distribution Networks: UC3 Latching Relays play a vital role in power distribution networks, ensuring compliant and secure switching to maintain the stability of the electrical grid.

Understanding the features of UC3 Latching Relays brings confidence to electrical switching applications, particularly in scenarios that demand compliance with IEC62055-31 standards, robust short-circuit current carrying capacity, and fault current making capacity. Embrace the reliability and precision of UC3 relays for confident switching in diverse electrical environments, where adherence to standards is non-negotiable.