WTL-A700 Crane Warning System for Accident Prevention

2022-10-12 15:00:53

Safe Load Indicator(SLI)[1] (which also called "Load Moment Indicator"(LMI) or "Crane computer") is a device which is installed on mobile, crawler, tower, gantry or portal crane. It alert the operator if the lift is exceeding the safe operating range. In some cases, the device will physically lock out the machinery in circumstances it determines to be unsafe. The SLI systems are usually composed of a microprocessor connected to various sensors on the crane itself.

The Safe Load Indicator SLI can measures the angle and extension of the crane boom along with the load weight and compares it with the manufacturer's specifications to determine if the lift is safe. A safe load indicator has the capability of detecting the working radius of the lifting device as well. It controls the lifting equipment to function as per the manufacturer's suggested safe load charts. Each of the measured parameters will then further be displayed in the operator's cabin.

Weite Technologies Co., Ltd has a lot of exeperience in both onshore and offshore crane safety protections. Its modernest WTL-A700 Safe Load Indicator has the following technical parameters and functions;  

1:Measurement Range:

•Weight Measurement Range: 0T~999.9T

•Resolving Ability: 0.1T

2:Measurement Accuracy:

•Combined accuracy: ±5%（F.S.）

3:Working Conditions:

•Working Voltage: DC24V ±10%

•Working Temperature: －20℃～60℃

•Relative Moisture: 90%RH（20℃）

•Action error: <±3%（F.S.）

•Relay contact capacity: DC24V 2A

4: IP code

•Load sensor: IP66;

•Angle sensor : IP66

•Load indicator : IP65

5: Preset Weight, Angle

Preset the weight you need and the rated weight and enter into the hoist according to the specifications of key operation method.

6. Function description:

A, Warning Function:

When the total weight is up to more than 90% of the rated weight, it sends out clear and obvious sound-light alarm signals (the yellow light warns);

B, Alarm Control:

When the moment is up to more than 100% of the rated moment, it sends a clear, obvious sound and light alarm signal (the red light alarms), meanwhile, it will output overload control and lower limit control;

C, Upper control limit:

When crane main boom luffing, the working range reaches to the minimum working radius (the maximum working Angle)specified in the load chart, the upper limit relay action, the buzzer alarms and the red light flashes at the same time. 

When the boom luffing approaches to 0.5m far away from the upper limit control point, relay action. It starts sound-light alarm.

D, Lower control limit:

When crane main boom luffing, the working range reaches to the maximum working radius (the maximum working Angle)specified in the load chart, the upper limit relay action, the buzzer alarms and the red light flashes at the same time. 

When the boom luffing approaches to 0.5m far away from the lower limit control point, relay action. It starts sound-light alarm.