How to calculate power units consumed

msankadi

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Hi

I have seen my electricity bill has gone up significantly since I bought my Epson TW9400 projector.

Can someone guide me on how I can calculate the number of power units consumed per hour by my projector in eco mode?
 
Hi

I have seen my electricity bill has gone up significantly since I bought my Epson TW9400 projector.

Can someone guide me on how I can calculate the number of power units consumed per hour by my projector in eco mode?
You may use a Smart Socket like "Wipro" to find exact power consumption.
 
Don't blame ur projector. Electricity bill is high for the last two months in Bangalore. May and June bills are 50% higher than usual. I think per unit cost increased .
 
Put a multimeter in current measuring mode, connect in series with your AC power cord and see how many amps it pulls when running. Disconnect. Put it in voltage mode and measure output voltage at your outlet. Current x voltage = watts consumed.
Be careful when playing around with AC voltages.
 
Hi

I have seen my electricity bill has gone up significantly since I bought my Epson TW9400 projector.

Can someone guide me on how I can calculate the number of power units consumed per hour by my projector in eco mode?
The number of units consumed that is in the bill is most important. The money paid is the multiplier of that and can vary due to changes in tariff, duties, tax, minimum due, load charges etc

If the units are similar for the past 3 years in the same month then nothing to worry. Also compare to the neighbouring months.

If you are worried about your line being tapped, switch your mains off and go down to see if your meter is still turning.
 
Please check the power rating mentioned on the projector. If should be there on the back label. The relative power rating of two appliances will give you rough idea of their power consumption level. for example, a 300 W rated appliance will generally consume more power than 100W, at comparable usage levels. If you already have a microwave or water heating rod in the home, then probably they consume more power than projector but factor in usage time also. Again, these are max power ratings. Calculating precise value of power consumed is not very easy on paper. The 'Unit' as mentioned in power bill corresponds to 'kilo Watt-hour' though. This formula can be applied straight away in case of DC by multiplying power with usage time in hours but for AC, other factors step in. You will see that appliance like AC and Fridge now a days come with 'Energy rating' sticker. It shows actual power consumption and energy efficiency (6 stars being most efficient). Not sure of projectors being energy intensive also come with such rating. Pl check the manufacturer website for that. Hope this helped. Regards
 
The number of units consumed that is in the bill is most important. The money paid is the multiplier of that and can vary due to changes in tariff, duties, tax, minimum due, load charges etc

If the units are similar for the past 3 years in the same month then nothing to worry. Also compare to the neighbouring months.

If you are worried about your line being tapped, switch your mains off and go down to see if your meter is still turning.
Yes my units has gone up by almost 100 in the past 2 months. It used to be around 200 and is now 300+. I stay in a multistorey society so tapping is not a concern

The max power in specs for my projector is written as 382w.now does this mean at max it can consume 1 unit in 2.5 hours? If yes,i think that is a good enough approximation for me and means it is very difficult for the projector to account for more than 50 units per month
 
What kind of lamp does your projector have? Incandescent/ halogen/ LED?
This is the link to my projectors specs. Does it help?

 
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Yes my units has gone up by almost 100 in the past 2 months. It used to be around 200 and is now 300+. I stay in a multistorey society so tapping is not a concern

The max power in specs for my projector is written as 382w.now does this mean at max it can consume 1 unit in 2.5 hours? If yes,i think that is a good enough approximation for me and means it is very difficult for the projector to account for more than 50 units per month
YES.

Your calculation is Perfectly correct.

Just keep in mind that this is the MAX possible power consumption.

In standby the consumption will be MUCH Lower.

In Mumbai, where I live, the electric company does not take meter readings every month. They assume an approx reading in a bill and then the next month when a reading is actually taken, it compensates for the approximation.
The approx reading is shown as "projected"

Do also keep in mind that Electric comsumption is typically higher in Summer Months due to increased Aircon usage.
 
From the tech specs you have posted:

355 Watt, 271 Watt (economy), 0.35 Watt (standby),
Yep that's how I was approximation it to 400w, roughly 1 unit(kwh) in 2.5 hours.

Is this calculation right or are their other considerations like efficiency, loss and as someone mentioned ac/dc?
 
This is the link to my projectors specs. Does it help?

Yes, thanks. This uses a ULP mercury arc vapour lamp which itself is 250 watts. So you can expect 1.41 times of that as normal power drawn.
 
Yep that's how I was approximation it to 400w, roughly 1 unit(kwh) in 2.5 hours.

Is this calculation right or are their other considerations like efficiency, loss and as someone mentioned ac/dc?
As I have responded in post #11:

"Your calculation is Perfectly correct"
 
Yep that's how I was approximation it to 400w, roughly 1 unit(kwh) in 2.5 hours.

Is this calculation right or are their other considerations like efficiency, loss and as someone mentioned ac/dc?
You are forgetting air conditioning. Most of the 400 W from the projector is heat so the AC has to work harder to get rid of that extra heat.
 
You are forgetting air conditioning. Most of the 400 W from the projector is heat so the AC has to work harder to get rid of that extra heat.
oh I use it without ac without any temperature issues here in Bangalore...in fact haven't installed an ac for the past 13-14 years I have been in bangalore
 
oh I use it without ac without any temperature issues here in Bangalore...in fact haven't installed an ac for the past 13-14 years I have been in bangalore
I had no idea Bangalore was this pleasant. Haha! I looked up and found that it is almost a km above sea level.
100 units is 250 hours of the projector. Maybe you are using louder sound with the projector without realizing. I usually have higher volumes when using my projector compared to my TV.
 
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