Reform content of backup protection for mining hoist hoisting winch

 

According to the 2023 Coal Mine Safety Regulations, the electric control of the transportation lifting winch needs to have the following functions:

 

1. Improving electromechanical control requires a dual line protection system;

 

2. The electronic control system should have a protection test record within one month.

 

This hoist is produced by Shanxi Xinfusheng Machinery Manufacturing Co., Ltd. This system is equipped with two sets of CPU315, but it is only controlled by master-slave mode. The control system belongs to traditional control, and according to the new coal safety regulations, it cannot achieve the dual line function.

 

After communication and negotiation, a renovation plan for this system has been made:

 

1、 Add a backup protection system;

 

2、 Replace the original protection sensor and seamlessly integrate with the old electronic control system. The new protection system should be able to meet the following requirements:

 

1. The display screen has a record of protection tests conducted within one month;

 

2. Meet the various protection functions of the hoist specified in the Coal Safety Regulations: overcurrent, overvoltage, overload, misalignment, gate clearance, over winding, depth failure, depth dual line, speed three line protection.

 

3. Equipped with remote diagnosis (main PLC) function, capable of remotely detecting the running status of the host, modifying programs and parameters, or monitoring through local area network.

 

4. The quality meets the relevant national standards.

 

5. Main technical indicators

 

Power supply voltage: AC380V

 

Environmental temperature: 0-40 ℃

 

Maximum depth display value: -999.9m~0m; 0m to 999.9m

 

Maximum speed display value: 9.9m/s

 

Backup protection function:

 

1. Up and down over roll protection

 

2. Constant speed section over speed protection (15%)

 

3. 2 meters/second over speed protection at the wellhead

 

4. Up and down deceleration point protection

 

5. Overload and undervoltage protection

 

6. Loose rope protection

 

7. Gap protection

 

8. Full warehouse protection

 

9. Depth indicator failure protection

 

Display memory function: For the above faults, there are sound and light alarms and memory faults.

 

Input signal voltage DC24V

 

Output independent node capacity AC220V, 1A (resistive load)

 

Maximum number of ticks memory function: 999 ticks

 

（1） Installation and wiring

 

a) Stand the control display box next to the control console and adjust the height through the four lower legs.

 

b) Connect the AC380V power supply.

 

c) Install the rotary encoder using the connection device provided by the manufacturer and connect it to the low-speed shaft of the elevator, taking care not to produce radial runout.

 

d) Install the zero position Hall switch at the edge of the drum, ensuring that the position of the magnetic steel matches the zero position at the wellhead. The wellbore switch is installed at the appropriate position of the wellbore according to the position of the up and down parking points. The transmission cable specification is 2 * 1.5, and it must be a qualified signal cable product with a coal safety license.

 

e) Connect the loose rope, full bin, and skip switch contacts according to the schematic and wiring diagram; Connect the overload and undervoltage signal from the auxiliary contact of the air switch in the electrical control system of the hoist; Connect the contacts of the upper and lower wellbore switches and the upper and lower deceleration switches.

 

f) The gap switch is installed on the disc brake support of the hoist, and the switch contact is attached to the back of the brake disc. Use a multimeter to measure the normally open contact of the switch, and gently push the switch forward. When the normally open contact is just closed, tighten the switch. The action gap of the switch should be less than 3mm.

 

g) Connect the safety protection relay contact AQJ to the safety protection circuit of the hoist electrical control system.

 

h) Connect the upper and lower over roll relay contacts SGJ and XGJ to the over roll protection circuit of the hoist electrical control system.

 

i) Connect the upper and lower deceleration relay contacts SJJ and XJJ to the deceleration circuit of the hoist electrical control system.

 

j) Connect the grounding terminal to the workshop grounding grid, and the grounding resistance should be less than 4 Ω.

 

 

（2） Parameter setting and calibration

 

Depth indicator parameter settings:

 

In the depth indicator parameter setting, all parameters are measured in meters. We have made the following limitations in software programming:

 

The designated parking point at the wellhead is 0 meters, with an increase in the lowering number and a decrease in the raising number. A number less than 0 meters is a negative number. The actions of over coiling, up deceleration, and up parking are all actions that occur during upward operation. The actions of over coiling, down deceleration, and down parking are actions that occur during lowering. By understanding this regulation, you can set the parameters for each point according to the actual situation.

 

Maximum depth: represents the maximum lifting stroke of the hoist, in meters. This parameter also determines the range value of the depth bar graph in the operation screen.

 

Given speed: represents the rated speed of the hoist. Unit: meters per second.

 

Overroll protection position at the wellhead, usually negative. Unit: meters.

 

Under roll protection point: the position for over roll protection in the underground parking lot. Unit: meters.

 

Up deceleration point: The distance at which deceleration begins when lifting Unit: meters.

 

Downward deceleration point: The distance at which deceleration begins when lowering. Unit: meters.

 

Upper parking point: the accurate parking position during lifting. Unit: meters.

 

Lower parking point: The accurate parking position when lowering. Unit: meters.

 

2 meter over speed point: The distance at which 2 meters/second over speed protection needs to start when running to the wellhead. Unit: meters.

 

Upper parking pulse: When in the upper parking position, install the wellbore switch. At this time, the corresponding rotary encoder pulse reading can be read in the "Display Value" column of the "Depth Indicator Calibration Screen", which is generally zero.

 

Lower parking pulse: When in the lower parking position, install the lower wellbore switch. At this time, the corresponding rotary encoder pulse reading can be read in the "Display Value" column of the "Depth Indicator Calibration Screen".

 

 The schematic diagram of each point is shown in the following figure: