1. Application range

Overcurrent relays are used to distinguish the overload and short-circuit protection of power equipment such as generators, transformers, and transmission lines.

The low current relay is used as a blocking element for PT disconnection.

It can completely solve the defects of contact jitter, refusal to move when electromagnetic relays are operating, low setting accuracy, and return coefficients affected by residual magnetism. It can replace DL-31, DL-32 and DL-7 electromagnetic relays.

2. Model definition

3. Working principle and main performance

3.1 Working principle:

The AC current is converted by the converter to the AC voltage required by the series of relays; then the harmonics other than 50HZ are filtered through the 50HZ bandpass; then the DC voltage is sent to the tuning loop through rectification and filtering; the tuning loop depends on changing the amplifier's amplification Multiplier to change the setting value; the output voltage UZ of the setting loop is compared with the threshold voltage UB through the level detector; then the output of the relay J is driven to act.

3.2 Action process of low current and over current relay (take AK11 structure relay as an example):

3.2.1 For the over-current relay in normal operation, UZ＜UB, relay J does not act, the moving contacts 1-3 and 7-19 are disconnected, and the moving breaking contacts 3-17 and 5-7 are closed; In the case of UZ≥UB, the relay J will act, the moving contacts 1-3 and 7-19 are closed, and the moving breaking contacts 3-17 and 5-7 are disconnected.

3.2.2 For low-current relays, under normal operation conditions UZ>UB, relay J does not operate, the moving contacts 1-3 and 7-19 are disconnected, and the moving breaking contacts 3-17 and 5-7 are closed; In the case of failure, UZ≤UB, relay J will act, moving-on contacts 1-3, 7-19 are closed, and moving-break contacts 3-17, 5-7 are open.

3.3 The use of high-efficiency integrated circuits and components, with stable performance, high reliability, high accuracy of the action value, small discrete value, wide setting range, fast action and return speed, good return coefficient, small load on the transformer, and vibration resistance , Anti-interference and high insulation level.

3.4 The protection setting value is set by the dial switch on the relay panel, and the setting calculation formula is indicated. The setting is intuitive and convenient, and the debugging is simple and convenient. No adjustment is required on site.

3.5 The product installation structure includes embedded board rear wiring and protruding board front wiring as well as standard 35mm rail type terminal block wiring, which is convenient for on-site installation and has strong versatility.

4. Technical conditions

4.1 Environmental reference conditions

Environment temperature: 20±2℃

Relative humidity: 45%～75%

Atmospheric pressure: 86～106Kpa

4.2 Normal use conditions

Ambient temperature: -10℃～+50℃

Relative humidity of environment: not more than 90%

Atmospheric pressure: 80～110KPa

Limit temperature during storage and transportation: -25℃～+70℃

The altitude of the place of use: no more than 2500 meters

The surrounding medium in the use environment has no explosion hazard; it does not contain corrosive gas; the concentration of conductive dust contained should not reduce the insulation level below the allowable limit value.

4.3 Rated parameters

Rated AC current: 5A, 1A

Rated frequency: 50HZ; 60HZ

Auxiliary power supply rated voltage: 220VDC; 110VDC; 48VDC; 380VAC; 220VAC, allowable voltage fluctuation range: 0.8 to 1.15 times the rated voltage.

4.4 Characteristic parameters

4.5 Maximum power consumption:

AC current loop: each phase is not more than 0.5VA at 5A; each phase is not more than 0.2VA at 1A.

Auxiliary power supply: not more than 6W at 220VDC; not more than 10VA at 220VAC

4.6 Maximum capacity of contacts:

Cut-off load capacity: DC 250V or less, τ=5ms, inductive load 50W, resistive load 150W;

AC below 250V, load 1200VA;

Allow long-term connection current: 5A.

4.7 AC circuit overload capacity:

AC current loop: continuous work under 2 times the rated current;

It can work for 10S under 10 times of rated current;

It can work for 1S under 40 times the rated current.

4.8 Insulation resistance: Use an open-circuit voltage 500V megger to measure the insulation resistance between the exposed non-charged metal parts or shells of the relays connected to each conductive terminal and should not be less than 10MΩ.

4.9 Insulation withstand voltage: each lead-out terminal to the housing locking screw can withstand a power frequency voltage of 2000V, and the same group of contacts can withstand a power frequency voltage of 1000V, which lasts for one minute without breakdown.

4.10 Anti-interference performance: meet the national GB6162-85 "Electrical Interference Test of Static Relays and Protection Devices" standard.

4.11 Electrical life: In the DC250V circuit, cut off the current τ=5ms, 50W, more than 104 times.

4.12 Mechanical life: The contact is 3 million times in no-load state.

5. Structure type (see the relay structure size diagram for details)

5.1 The rear wiring structure of the embedded board AK11, AP11 and the rear-view wiring diagram of the protruding board front wiring AQ11 (subject to the company's product samples)

5.2 JK-1/8 structure rear view wiring diagram (subject to company product samples)

5.3 DZ-1 structure terminal block type terminal wiring diagram (subject to company product samples)

6. Use

6.1 Before energizing the relay, confirm whether the voltage level of the connected relay is consistent with the actual parameters, otherwise the relay may be damaged; check whether the relay is damaged during transportation and storage, and the relay screw fasteners should not be loose; if there are damaged parts , Please contact us to replace it for you.

6.2 Use the dial switch to set the action value according to the formula on the relay panel.

Relay setting formula: I=K*[□+0.1*□+1]A; K value depends on the setting range

When the current range is 1～10.9A, K=1 I=[□+0.1*□+1]A;

When the current range is 2～21.8A, K=2 I=2* [□+0.1*□+1]A;

When the current range is 5～54.5A, K=5 I=5*[□+0.1*□+1]A

7. Ordering instructions

When ordering, please specify the relay model, specification, quantity, auxiliary power supply, coil AC rated current, structure and other requirements.