Parking Detector Low Power Test Solution

The parking space detector is a key component of the intelligent parking system. In the standby state, the current is as small as 20μA. In the transmitting state, the current is up to several A. The parking space detector is mostly powered by the battery. The power consumption is very high, and the standby current is biased. Small and current wide range hopping makes power consumption testing difficult. This article mainly introduces the PA310 power meter's solution for power consumption testing difficulties.

This article refers to the address: http://

With the rapid growth of domestic automobiles, the problem of fewer vehicles is becoming more and more prominent, and it has become a common concern in the current society. The emergence of intelligent parking system can maximize the utilization of parking spaces, create an orderly environment for on-street parking, and solve the problem that the parking spaces are difficult to find for the owners.

Introduction to the principle of intelligent parking system

The road intelligent parking system is composed of geomagnetic parking space detector, repeater, concentrator, data processing center, city parking space induction, etc., integrating parking space monitoring technology, information release technology, and Internet of Things integration technology to maximize the use of parking spaces. Improve the convenience of citizens' travel and provide effective data protection for urban parking space monitoring and planning. The system architecture diagram is as follows:

1.jpg

The wireless geomagnetic parking space detector uses a magnetic sensor to detect the influence of the vehicle on the geomagnetism in real time to determine whether there is a vehicle parking on the parking space, and transmits the detection data to the repeater by wireless, and the repeater receives multiple wireless geomagnetic vehicles. The information sent by the detector is uploaded to the concentrator, the concentrator manages a range of parking space detectors and repeaters, and the collected parking space status data is uploaded to the monitoring center for centralized management.

Power test analysis

The parking space detector is used as the front end of the digital 椐 acquisition. The magnetic sensor is used to detect the influence of the vehicle on the geomagnetism in real time. When there is a vehicle stopping, the magnetic field distortion is different to judge, reflected in the electric signal, when no vehicle passes, the parking space detector When the work is in the standby state, the standby current is below 20μA. When the vehicle is detected, the detection number is required to be uploaded to the concentrator. At this time, the parking position detector works in the transmitting state, and the current is up to several A, as shown in the following figure:

2.jpg

In this case, the power consumption test of the parking space detector is a major difficulty. First, the standby current is too small. Take the PA310 power meter of Guangzhou Zhiyuan as an example. The minimum range of the PA310 is 5 mA. The minimum measurable precision current is the range of 1 %, ie 5mA*0.01=50μA, the standby current cannot be tested directly with the PA310. At the same time, the difference between the standby current and the emission current is large. In the automatic range mode, the power meter rises from a small current to a large current, which is gradually traversing the middle. The range is a waste of time and affects the accuracy of voltage and current integration. However, the parking space detector is battery-powered and has strict requirements on power consumption specifications and battery power supply time at the factory, so accurate power consumption testing is very important.

Power test scheme

When the parking position detector is in standby mode, the standby current is as small as 20μA. The PA310 power meter is used directly, and the minimum gear position is set to 5mA. The minimum precision current that can be tested is 50μA, and the standby current cannot be accurately tested. Set the constant current source as follows:

3.jpg

Set the constant current source output constant current value (such as 50μA), superimpose the current value and the current of the parking position detector, then input the PA310 power meter to measure, and set the integral mode to test the voltage and current integral value for a period of time. The power consumption of the constant current source is removed, and the power consumption of the parking space detector for a certain period of time is calculated. At the same time, since the difference between the standby current and the emission current is large, during the measurement process, the range skip function is enabled, and the current range can be directly skipped to the specified range, which can reduce the measurement data loss when switching ranges one by one. Improve power measurement accuracy. (Note: Since the internal resistance of the PA310 power meter is mΩ, the current can be introduced by means of an external power supply + MΩ precision resistor instead of the constant current source).

In consumer electronics and wireless mobile devices, battery power is required to be greener and more energy efficient, and high sensitivity, low current measurements are increasingly needed to ensure that the current consumption of these devices is within acceptable limits. In order to maximize battery life, engineers need to minimize power consumption during the life of the product. The low-power test solution for parking space detectors provided above meets the requirements of external current sources and set-range skipping. The need for small current measurements with a wide dynamic range.

Din-Rail Terminal Blocks

The Din-Rail Terminal Block is used to facilitate the connection of wires. In fact, it is a piece of metal sheet sealed in insulating plastic. There are holes at both ends to insert wires and screws to fasten or loosen them. For example, two wires sometimes need to be connected and sometimes need to be disconnected. This can be connected with terminals and can be disconnected at any time without them It's very convenient and fast to weld or wind together. And it is suitable for a large number of wire interconnection. In the power industry, there are special Terminal Blocks, terminal boxes, all of which are terminal blocks, single-layer, double-layer, current, voltage, common, breakable, etc. A certain crimping area is to ensure reliable contact and enough current.

Insulation material is nylon 66 with good flexibility and flame retardant , copper alloy with wire frame structure provide moisture, salt fog and bad environment protection for a long time, special wire pressing structure have good self-locking and loose proof performance. the product designed in accordance with IEC60947.

Din Terminal Block,Din Rail Terminal Blocks,Rail Mount Terminal Block,Din Rail Terminal Block Connector

Suzhou WeBest Electronics Technology Co.Ltd , https://www.webestet.com