How WH57 Lighting Sensor Works

1. What is lightning and how is it monitored?

The changing electric charges in the clouds produce lightning, lightning affects the strength of the electromagnetic field, and changes in the strength of the electromagnetic field produce electromagnetic waves. Electromagnetic waves caused by lightning discharges can travel hundreds of kilometers, and sensors can be used to receive lightning electromagnetic waves and send out alarm signals to warn of lightning. The technique of monitoring lightning through electromagnetic waves is capable of monitoring large lightning strikes, but a lightning strike warning is not issued until after the first strike. This lightning monitoring technique is more seriously affected by electromagnetic interference nearby. Currently, this technique is mainly used for lightning strike location and sensor distance or lightning localization, if more than one sensor receives a lightning electromagnetic wave, can be used to calculate the location of a lightning strike by time difference method.

The WH57 is a sensor capable of detecting lightning discharges in the atmosphere, including lightning between clouds and the ground. The WH57 can detect lightning activity over a distance of 40km.

2. WH57 technical principles

After the WH57 receives the signal from the outside and amplifies it, the lightning algorithm block in the sensor first distinguishes the signal into a lightning signal and a man-made disturbed signal. If the received signal is categorized as a man-made disturbed signal, the signal will not flow to the next module and nothing will be displayed on WH57. If the received signal is categorized as a lightning signal, the signal flows to the next module to record the storage of this lightning strike and to estimate the minimum distance from the sensor to the nearest edge of the storm (which does not represent the distance to a single lightning bolt).

The signal amplification function described earlier is performed by the Analog Front-end(AFE) in the WH57. The default AEF gain applies indoors; if the WH57 is operating outdoors, the AFE gain setting must be set to a lower value. The gain level must be selected according to the product application environment, such as indoor and outdoor, and the switch above the battery is toggled to the appropriate position. The signal verification module in WH57 checks the shape of the received signal, and if the shape of the signal does not conform to the typical shape of a lightning signal, the signal is determined to be a man-made disturbed signal, such as a spike. This feature of the WH57 suppresses similar interference while missing some lightning strikes.

3. Possible problems and solutions when usingWH57

(1) No lightning, but WH57 lit up

1. If the product is indoors and operations such as switching on/off the lamp/plugging in/out the power adapteraffect the measurement of the product, check that the flickering of the WH57 is not caused by operations such as switching on/off the lamp/plugging in/out the power adapter that generates electromagnetic waves.
2. If the product is outdoors, there may be electromagnetic waves caused by electromagnetic activity other than lightning in the area where the sensor is erected.After checking through the internet or other ways to make sure that there is no lightning activity within a 40km radius, first remove the battery from the WH57, flick all the switches on top of the battery to the bottom, then install the battery and test it along the perimeter of your house, if you find a place where you find that the WH57 won't flicker anymore without lightning, then you can install the product in that place. Readings are transmitted every 79 seconds, please stand still for more than a minute and a half during the test. It is best to use a rain cover when installing, while the WH57 should be at least 3m away from other transmitters or electrical equipment.
3. Before purchasing the WH57, you can listen to the sound by using an AM radio with the listening frequency tuned as close as possible to around the 500khz range:If there is a short disturbing sound similar to that of a lightning strike, your area may not be suitable for the use of this WH57 transmitter.

(2) Lightning but WH57 not detected

1. If the WH57 is placed indoors, please put it outside, perhaps your house attenuates the lightning electromagnetic wave, causing the WH57 not to be detected.
2. If your product does not monitor lightning even when placed outdoors, please test the function of WH57 to see if it is normal.Put WH57 near the lamp switch/ power adapter /gas lighter (non-electric flint lighter), etc. Turn on the lamp switch/insert the power adapter /light the lighter, WH57 lights up for 2s, it means the function is intact, if it doesn't light up, it's damaged, please contact the product after-sale.
3. The lightning signal fluctuations were not within the conditions that WH57 considered to be lightning fluctuations, and by failing to report the lightning strikes when they were mistakenly recognized by WH57 as disturbing signals, there was a reasonable range of error on the part of WH57.

For more details, see the chip specification. If it does not work around your home, the product is not suitable for you.

The sensor is recommended to be placed outdoors for use, as the device is susceptible to electromagnetic waves from electronics, and placed outdoors will be interfered to the minimum  by electronics indoors. It is also recommended to install it high off the roof or at least five meters away from your house.