Thermal relay calibrator use precautions - Solutions - Huaqiang Electronic Network

Use a power cord with sufficient safe current carrying capacity to turn on the 220V power supply with sufficient capacity, select each function switch to the required position, and rotate the output adjustment handwheel to zero position to connect to the device under test, and the instrument can start working. When the output current is large, a power supply with a small internal resistance should be selected. If the internal resistance of the power supply is too large, the output current is not easy to rise to the set value.

1, test thermal relay

The thermal relay cover should be covered during the test. The small current value thermal relay uses a small current gear position, and the three thermal components are connected in series, and then connected to the corresponding test column. The normally closed point is connected to the auxiliary contact column, and the range switch Select the appropriate current gear position, the output adjustment handwheel is set to zero position, the self-locking switch is disconnected, check that the contact of each terminal is good, turn on the power switch, press the start button, test the power on, rotate the output adjustment handwheel to be The rated current of the thermal relay is such that the bimetal reaches a thermal stable state, thereby stabilizing the hot state and then rotating the output to adjust the handwheel so that the test current reaches 1.2 times the rated current, the timing starts from zero, enters the test phase, and the heat is within the specified time. The relay should trip to the qualified one, the thermal relay contact is disconnected, the test current disappears, the timing stops, and the test time is displayed. The end of the test signal is given by the light and the sound. When the signal is to be stopped, the sound and light switch can be turned off.

When the test is rated, it is generally customary to start with the cold state of the thermal element. For other parameters of the thermal relay, please refer to the relevant regulations, or select the safety-secondary tripping characteristics of the thermal relay according to the protected motor load.

2, measuring circuit breaker, motor protector

Before the test, carefully check the active parts, whether it is rusted or stuck, and the moving shaft should have a small amount of lubricating grease. After the test is closed, the manual tripping is performed, and the instantaneous tripping is correct before testing.

The circuit breaker motor protector has the same auxiliary contact as the thermal relay. When the circuit breaker is disconnected, its signal is sent by the sensor of the shutdown device, the test power is turned off, and the test time is displayed, and the test completion signal is issued.

3, measuring semiconductor circuit breaker

Before the detection, the switch should check the above-mentioned mechanical mechanism and check the electronic components. The semiconductor switch has many functions such as long delay, short delay, instantaneous trip and undervoltage trip. The test lead can be placed on the transformer attached to the switch and then connected to the corresponding end of the instrument for testing. The DC voltage of the instrument can also be applied to the first two points of the circuit breaker signal detection distribution circuit, or according to the manufacturer. The parameters or the load condition of the protected equipment are measured.

4. This instrument can be used for proofreading of electrical and instrumentation instruments such as AC contactors, AC ammeters, and current transformers commonly used in low-voltage power distribution. For other relay protection devices and low-voltage electrical appliances, please refer to the relevant regulations, standards, load properties, etc. and the parameters given by the manufacturer.

5. The measurement switch is selected to the AC450V or DC300V voltage position, the voltage output switch is turned on, the self-locking switch is closed, and the rotary output adjustment hand wheel can obtain DC 0~220V on the corresponding terminal, and the AC 0~450V is continuously adjustable. Output voltage. (alternative function)

Fault analysis and elimination

1. Power is not available, please check if the fuse is blown and the plug is connected.

2. No output, see if the current transfer switch hits the neutral position, or see if the current riser has 220V input, whether it is due to oxidation of the output terminal.

3. There is no display output, and the current limiting resistor R1 or R2 is broken 353.

4. The sync signal does not work, the start button is damaged, or the 3DK4 is damaged.