SMN-1 ABB drawer switch cabinet contact clamping force detector

1、 Overview

Due to the widespread use of various low-voltage switchgear equipment in the power system, especially outdoor switches that are completely exposed to leakage and operate in the atmospheric environment, long-term exposure to climate conditions and harsh operating conditions can easily lead to mechanical and electrical failures. In particular, the contact part of the contact head is corroded by gas, resulting in poor contact and heating. The pressure spring of the contact head is annealed due to heating, leading to a vicious cycle of contact heating and ultimately burning out the contacts, resulting in accidents. During maintenance, only the obviously failed and broken contacts are replaced, and the spring contacts with reduced pressure cannot be compared and replaced. In this way, during long-term operation, the distribution of current in each contact will be different due to different pressures, and the greater the difference, the more uneven the current distribution will be, Poor contact of one contact can affect the normal operation of the entire switchgear and cause accidents to electrical equipment in operation.

The SMN series contact pressure detector uses 5V0 constant voltage excitation to power the 1-5K pressure sensing resistor bridge, and data is collected by an external 24 bit high-precision A/D under the same 5V0 reference. Select various measurement methods from the bilingual prompt software menu in both Chinese and English. After data processing, it is displayed on a high brightness green 12864 dot matrix active light-emitting OLED screen. And there is a buzzer reminder and dedicated green and red OK and OUT lights to indicate whether the output result is qualified or not. It is a specialized measuring instrument used to check whether the contact pressure of power equipment is qualified.

Instrument working mode:

According to the settings, the measurement and display contact pressure can be calculated in three ways: "key measurement", "automatic", and "continuous".

The comparison type and upper and lower limits are entered into RAM by 24LC64 during startup to determine whether the contact pressure is qualified.

If it is qualified, the buzzer will beep for 0.5 seconds and the OK green light will remain on, and the measurement value will be displayed on the main screen.

If it is not qualified, the buzzer will beep three times rapidly and the OUT red light will be on for a long time to give an alarm. The measurement value will also be displayed on the main screen

SMN-1 ABB drawer switch cabinet contact clamping force detector

2、 Product Features

1. Multi functional display screen

2. Convenient bilingual four key operation interface, and dedicated one touch keys can be used to complete measurement operations.

3. Freely customizable measurement and judgment methods

4. Concise calibration method

3、 Technical indicators

The main technical specifications of the SMN series contact pressure detector are:

4、 Description of each functional component

5、 Parameter settings

1. The working interface of the detector is shown in Figure 1

The working interface of the integrator includes five interfaces, with the first screen being the main interface and the second screen being the auxiliary interface.

The main screen interface is shown in Figure 1:

Figure 1: Main Screen Interface

The measurement result is generated by pressing the test button or inserting the probe in automatic mode, and the result is displayed approximately every 3 seconds in continuous mode.

The zero point calibration of the second screen is shown in Figure 2:

Figure 2Zero point calibration and zeroing interface on the second screen

When the test head is empty and not loaded, enter the password "10" to complete the on-site zero calibration and reset to 0.

The auxiliary interface of the third screen is shown in Figure 3:

Figure 3 Third screen auxiliary interface

Enter the password "22" or "33" to enter the user or engineer menu respectively.

2. Display of working status

After the power switch is turned on, the instrument first self checks and enters the main display state of screen 1 after completion.

2.1 Switching between work screens

press “<” Press the key or "+" to switch between the main work screen 1 and the auxiliary work screens 2 and 3.

2.2 Button measurement method

After pressing the "Test" button, clear the screen values and results and turn off the traffic lights. Then, perform a set of sampling calculations and comparisons, and display the new measurement results after a delay of 0.5 seconds.

2.5 Parameter Settings

In the state of display screen 3, the text prompts "Enter password". Use the "S,+, ◄, E" key combination to enter the password.

E "key: Enter the initial password input state. S "key: Cancel input mode and return to the main screen display.

Press the "+" key in input mode to cycle through the values 0-9 and symbols at the cursor.

Press the "<" key in input mode to move the current input cursor position.

Press the "E" key in input mode to bring up the cursor or confirm saving parameters.

If it is correct, enter the menu; if it is incorrect, return to the initial input state.

Zero point reset password: 10

User menu password: 22

Engineer menu password: 33