How can I calculate electricity usage

[Shaun @ Tru6]

For my Cerakote curing oven, I normally turn it on and get it to 250F which takes about an hour. Opening the face/door and loading it cools it down to 80-90 (air) and then it's about 30 minutes to 250F again and then 2 hours for bake.

You can also run Cerakote at 300F for 1 hour. Tried that today. Took just under 2 hours to get to temp, down to 80 (air) loading and then 1 hour back to 300F and then 1 hour for curing.

My sense is it's cheaper to run it at 300F. How can I calculate the electrical draw while it's warming up? It's fairly stable, turning on and off, to maintain temp though I haven't recorded how many times and how long each time it does turn on to maintain 250 or 300 over a period

[KFC911]

I'm no help....mebbe ask a cashier

[BK911]

Logging inductive amp meter installed in electrical panel.

[Hugh R]

Do you have a smart electrical meter? You may be able to log into the account to see real time usage.

[porsche930dude]

I would shut everything else off and see how much the meter goes round. Anything else is gonna cost money

[Sooner or later]

Originally Posted by porsche930dude

I would shut everything else off and see how much the meter goes round. Anything else is gonna cost money

That was my first thought

[dad911]

Clamp on amp meter will tell you current draw.

To convert to watt-hours, you need to know duration (time) it is on. If you want to hack, find an old style analog clock, and wire it into the system. As I recall you had relays turnig on 220v heaters?

Or this should work: https://www.amazon.com/Electric-Meter-100A-Volt-3-Wire/dp/B00GMZRXE8

Maybe this?(not lot of info in description) https://www.amazon.com/dp/B07JB9B2QL/ref=sspa_dk_detail_3?psc=1&pd_rd_i=B07JB9B2QL&pd_rd_w=qUfiM&pf_rd_p=8a8f3917-7900-4ce8-ad90-adf0d53c0985&pd_rd_wg=I8TaP&pf_rd_r=TDPM0ZC1BYZP5Z1TZGGV&pd_rd_r=d2a5a5fa-6a06-11e9-8627-41445435c50e

Here's another: https://www.amazon.com/dp/B00A4VF7U8/ref=psdc_14244481_t1_B00GMZRXE8

[Shaun @ Tru6]

Originally Posted by dad911

Clamp on amp meter will tell you current draw.

To convert to watt-hours, you need to know duration (time) it is on. If you want to hack, find an old style analog clock, and wire it into the system. As I recall you had relays turnig on 220v heaters?

Or this should work: https://www.amazon.com/Electric-Meter-100A-Volt-3-Wire/dp/B00GMZRXE8

Maybe this?(not lot of info in description) https://www.amazon.com/dp/B07JB9B2QL/ref=sspa_dk_detail_3?psc=1&pd_rd_i=B07JB9B2QL&pd_rd_w=qUfiM&pf_rd_p=8a8f3917-7900-4ce8-ad90-adf0d53c0985&pd_rd_wg=I8TaP&pf_rd_r=TDPM0ZC1BYZP5Z1TZGGV&pd_rd_r=d2a5a5fa-6a06-11e9-8627-41445435c50e

Here's another: https://www.amazon.com/dp/B00A4VF7U8/ref=psdc_14244481_t1_B00GMZRXE8

Very cool gadgets, thank you! I'll research these more and get one. I think one of these will help a lot.

I forgot to say, a shop wants to use the oven to get to 400F for some other type of curing. I said I would just charge for electricity. Hope one of these gives me an answer for them.

[OldSpool87]

Try Onset. I used to track usage of a sump pump years ago.

https://www.onsetcomp.com/learning/catalogs

[dad911]

Originally Posted by Shaun @ Tru6

Very cool gadgets, thank you! I'll research these more and get one. I think one of these will help a lot.

I forgot to say, a shop wants to use the oven to get to 400F for some other type of curing. I said I would just charge for electricity. Hope one of these gives me an answer for them.

In that case, I would read meter at the beginning and end of a typical day when you don't use the oven, to get a benchmark. Then repeat while oven is on for them, and subtract the "benchmark".

[BK911]

Most fluke meters have a data logging feature.
This one can connect to your phone, so your phone logs the data.
Amp convert directly to $s.

https://www.transcat.com/brand/fluke-store/fluke-clamp-meters/fluke-374-fc-fluke-374-fc-253942

[Tobra]

seems like you should bake more parts per load.

[Superman]

My $0.02 (no instruments were used):

First, I assume the heat is all electric.....'strip' heater.'

During warm-up, all the strips are on all the time. During 'bake,' the strips turn off for at least part of the time. So....

Using the '250' option, one hour of strip-on-all-the-time is saved, compared to the 300 option. This is savings.

Now....strips come on and off during 'bake.' If the 'strip on' time for the 300 option (during baking, not warm-up) is LESS than one hour more than the 'strip on' time for the 250 option, then the 300 option uses less KVA/H. If the 'strip on' time for the 300 option is more than one hour more than the 250 option, then the 250 option uses less power.

I suppose it all depends on how well the oven retains heat.

[RKDinOKC]

My electricity has a login that I can get hourly my usage.

I look at usage with a device off over a certain time period.
The compare it to the device being used.

Have a wattmeter the plugs into the wall, then plug the deivice into it. Tells what the devices uses.

But never used it since just reading the usage graphs works well. Besides the meter is 120.

[Shaun @ Tru6]

Quick note to say I haven't bought any of the gadgets yet but have run the oven twice under two different circumstances and was amazed at the meter results.

4 hour total run time. 1.8 hours to get to 300F. Open and load. 1 hour to get back to 300, 1 hour to run at 300. kWh used: 30. That is SHOCKINGLY low. That equates to about $4. $4 Plus delivery so let's call it $8.


5 hour total run time. 1.25 hour to get to 250. Left it running because I was still shooting Cerakote. Open and load. 35 minutes to get back to 250F. 2 hours to run. kWh used: 33.

I basically took a pic of the meter outside, started the oven, took a pic at reaching initial temp and then one after the final bake.

I think I have to get one of those devices now though the meter can't lie.

[jcommin]

Do you have data showing the bonding characteristics:

250F @ 'X" time

300F @ "y" time

What is the PMT (part metal temperature) required to cure the coating? For example: if the PMT required is 200F, the time to get the part to temperature will be faster if the oven temp is set at 300F rather than 250F.

You can clearly see the relationship if you have a thermocouple monitoring the air temp and a thermocouple bonded to a steel substrate. You can clearly see the air and part temp profiles. You can look at the ramp up time, and also check the integrity of the electric heaters by comparing profiles over time.

https://www.flukeprocessinstruments.com/en-us/products/thermal-profiling-systems/datapaq-oven-tracker-systems

[jcommin]

Once you optimize the process time, then you can calculate your energy consumption.

[Shaun @ Tru6]

Jim,

Cerakote cures at 250F for 2 hours or 300F for 1 hour. There is a thermocoule hanging in the center at feedback to the controller for the two heating elements. Circled here.

I know I am getting 100% cure based on destructive testing of finished parts, that is to say Cerakote is really hard to destroy.

So both of my above scenarios work in terms of time against temp if I understand you correctly.

[wdfifteen]

I assume Cerakote requires specific substrate temperatures. You really need thermocouples on the parts if this is the case.

[jcommin]

Shaun - understood. what is the substrate doing?

For instance. I have a gasket product that needs to see a 325 F at the steel core for 3.23 minutes. The oven set point temperature is 435F. Using datalogging, I can monitoring the ramp time of the gasket product until it reaches 325 F and monitor the 3,23 minute time as it sits in the oven. The temp of the product continues to rise trying to reach the oven set point temp until I pull it out of the oven. I have a timer telling me when the the process is done. The bigger the gap between the PMT of the part and set point temperature, the faster the ramp up time and shorter overall process time. There are diminishing returns too. You want to be sure you work within the Cerakote material.

I use data logging for several reasons:

It checks the integrity of the oven, The thermocouple you point out will fail - how do you know it is accurate?
If my product fails to meet the PMT during this time period, I have a problem with the oven.
Historical data collecting.
Optimizing the time/temp process.


I removed an existing oven that dried a solvent based adhesive on steel and aluminum parts. It took 45 minutes to dry the parts. The adhesive is a bonding agent for rubber molding. My new oven takes 8 minutes. Consistent temperature and air flow. I did allot of testing with time/temp to optimize the process.
When I calculate savings, it was a combination of process time, scrap, labor, materials and energy.