Factory making XJM7 Measuring Box (Low Voltage Power Measurement Box) to Costa Rica Manufacturers


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XJM7 series of lighting Power metering box is suitable in power centralized measurement management of apartment buildings office buildings. Pulse-type power meter can be installed  to according to the design needs to achieve computer management. Besides, proper location is preserved to install remote-measuring remote sensing equipment. There are small circuit breakers installed in the cabinet to protect the line from overload, short circuit. The power meter and circuit breaker rated current are selected by design.

In line with GB7251.1-1997 and 7251.3-1997 standards.

3C certificate:

XJM7 Measuring Box (Low Voltage Power Measu-2

How to Connect Headlight Warning Relay

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The purpose of this circuit is to have a way to know whenever your headlights, brakes or turn signal light bulbs go bad. How many time have you been stoped by a patrol or simply just noticed that one of you lights, front or rear, was out. Light bulbs have an important role to play in our vehicle signals. But, there are very few vehicles with the ability to signal you whenever one goes bad. I should warn you that this system will not work on the very new L E D lights, nor do they work with H I D or high voltage systems made of Zenon gas.

The idea behind this circuit is to send a low current through the bulb filament, which is limited by the relay coil to 300 milli Amps. So long as the filament is good, the relay is activated. In the even that the filament breaks, then circuit is interrupted and the relay triggers the indicator light ON. Although we show this circuit here servicing only one headlight bulb, it is possible to use this circuit in series to service all the other bulbs as well. All we’ll have to do is change the value of the resistor and get a bigger diode.

This circuit has one diode, which is used to make sure there are no ghost or erroneous relay activations. It also has a 20 Ohm resistor to act as a current limitter. The resistor makes sure no excessive current flows in the event that the relay coil shorts. Otherwise, the headlights or whichever light bulb this circuit is connected to, may come ON inarventedly. The circuit then uses a panel warning light to alert the driver that a light is out.

Here is how the circuit works….. Get the whole story right now in this video, right here on this channel…Enjoy…

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