Light intensity monitoring

Tough I made connections as you said. My bolt device is getting heated up very fast, as soon as I supply power using a USB cable.
this happened when I was trying to my 1ST project light intensity monitoring.

Hi @sirishareddy762:

The Bolt WiFi module has a voltage regulator and an ESP8266 chip on them, which often tend to get heated up.
This is normal for the chip for a certain temperature range, which most people feel is excessive.

Do not worry if the module heats up too much.

If however the Module stops working as it should, please send an email to
Your device may still be in the warrenty period and Inventrom will send a replacement for the same if it is not working as it should.

Thank you @vinayak.joshi

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Hello, when I started my light intensity project , I could monitor some readings. However, I do not understand the meaning of the values. I see 1.02 thousand when there normal tube light, 829 when I put flash light over it and and 694 when I cover ldr with finger. what are these readings and how should I consider it. Can any one please help me with this?

The LDR sensor’s maximum value is 1.02 thousand and if you vary the light in your room it will vary only from 0 to 1.02 thousand.Since u have got variable readings your values are correct.

But mam what is unit of these values
What these values signify…?


Resistance of the LDR varies exponentially with light level (illumination intensity), which leads to the A0 pin saturating at 1023 even at moderate light levels. But, in poorly lit situations, you can see the difference. A0 then, will be a value less than 1023 (or 1.02 thousand so as to be precise).

More information regarding the value “1.02”-

The A0 point is the analog point and it takes in the value of voltage between 0 to 1.The taken value say 0.576V is converted to a binary number of 10 bits,by the in built ADC converter.So each value read by A0 pin is given by 10 bit binary number whose decimal equivalent ranges from 0 to 2^10-1(this decimal equiv. is shown in the output table).
Now in our case at bright light LDR,resistance lowers down and it gives less drop so A0 pin gets high value.For dark case resistance increases,and gets good drop so A0 pin gets low value.

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I connected all the hardware accordingly, and also wrote that one line of code as follows:
where ‘light’ is the variable assigned to pin A0.
but on viewing the data, it gives me this error:
“Please check your product code at line 167, character 117
Uncaught ReferenceError: hbspt is not defined”

I only have one line of code.
Ca you knindly help me with this?


yes,when i made it first then the same thing happend with me but later it was right on hins own.
just keep trying . ggod luck.

Sir, for plant monitoring project, is it safe to keep the bolt iot device in sunshine for extended period of time? Wont the sunshine or heat damage device or should I cover the device with some kind of shade and leave only LDR exposed to the sunshine? Please suggest.

I faced a similar issue, to resolve it, first try to make all the connections again and make sure that you’ve used the correct resistance. After that, try to dim the lights of your room to the minimum and get a reading. Most likely you’ll get a low rating of approx 200 units.
The range of the LDR is not very high for 10k resistance and even the light from your laptop in a dark room can give a rating of 1.02 thousand, so don’t worry if the chart is only showing 1.02k in a lit room.

1.02 thousand stands for 1023 that is maximum reading for a 10 bit analog device which corresponds to maximum intensity of light your LDR can sense

Hello Ravi Teja ,
When you see 1.02 thousand , it is the maximum value this LDR sensor. When you gradually decrease light in your room then you will see that the LDR sensor’s value also start decreasing , when you cover the LDR sensor with finger then sensor will give low value like 50 to 100. But if you not getting these values , I request you to please check the connection one more time or replace the resistor with 330 KOhms and try again.