stove plate

[murdock]

ever wondered how long it takes for your stove plate to get hot and what temperature it gets up to...i was getting familiar with the upgrade software for my fluke 189 and 289.

i had a hob in for repairs so when i finished repairing it...i connected all my test eqipment ran load tests and temp tests on each plate...scanned it with the thermal imager which i thought would be within the parameters...but when i got to 350 degrees c and went out of scale i connected the 289 and 189 with the temp probes and measured...well ever wondered why you get burnt so bad when you touch it....it gets to 525 degrees c... and takes 15 minutes from 33 to 525 on a standard 8 inch plate...drawing 6.4 amps...so now you can do your maths on the energy used for that period of time.

and becareful it takes the skin off your finger if you touch it...ask me i touched it by mistake...NOT ... i wanted to feel how hot 525 felt...not a clever idea...even the ice took a while to cool it down...my finger.

[murdock]

this is the screen shot of the temp.

[murdock]

this is an example of the most basic recorder we use...the fluke 289 with fvf.

also tested my new investment today a set of 3000 amp flex clamps today for my metrel 2192 power quality analyser...now i cover the full range...5 amp...1000 amp standard type current clamps and now 30...300 and 3000 amp in the flexible current clamps for the metrel unit...this unit only has sets of 3 clamps which means i can only measure 3 phases and it calculates the neutral.

200 amp standard and 3000 amp flex for the fluke 435...this unit is a class 1 unit and measures all 3 phases and the the neutral...it has 4 current clamps and measures the actual reading of the neutral.

i am now just waiting for my black box...the new circutor er3 which is gona be for doing load profiles and energy management profiles

slowly slowly its all coming together...it has taken me a couple of years to learn and understand how to use use the equipment but as i have been learning i have been getting valuable experience...i believe experince is worth more than all my certificates on my office wall...but it nice to have them to make people think you are smart

[daveob]

drawing 6.4 amps...so now you can do your maths on the energy used for that period of time.

so is that 220 V x 6.4 A = 1.4 kWh of juice, so cost about R1.50 per hour to run ?

[AndyD]

I think it might be better to log the current flow compared to temperature over time. The resistance of the plate could change quite noticeably given the wide temperature range, the kilowatt rating marked on it is a nominal value....not to be trusted:-)

[murdock]

http://www.eskomdsm.co.za/quick_energy

this might interest some people...i did the energy audit for my house and boy something doesnt add up because according to their audit i should be using about 300 kw of power but this is incorrect or my bill tells me i am using 800 kw maybe i should connect one of my loggers to my own meter and test it

dave your electricity cost about 65 cents per kwh...

our electricity should be 230 for calculations 230 x 6.4 = 1472 watts /1000 to give you kilowatts =1.472 Kw x .65 = 96 cents.

heating should have a PF of 1 but energy saving lamps i have tested are as low as 0.2...your washing machine...motor pumps etc also have a lower PF.

if you live in a house which has 3 phase power make sure your electrician has done a load profile for a min. period of seven days to check your load is as well balanced as possible to save you money.

i have watched many articles on PF correction for single phase installations for swimming pools etc but i have not done any investigations into ths type energy saving...my thought is it should save and if not will improve other aspects of the electrical installtions.

a customer called me the other day about a program he had seem on TV about energy saving load balancing and load profiling...i dont have dstv...toooo poor to afford it...so i havent seen it...anyone know about this program.

[murdock]

I think it might be better to log the current flow compared to temperature over time. The resistance of the plate could change quite noticeably given the wide temperature range, the kilowatt rating marked on it is a nominal value....not to be trusted:-)

could give you an exact reading if i link up the power meter...but i have already repaired and replaced the hob...they wanted it for easter weekend if i had known we needed to run more tests i could have told them the stove would only be ready next week tuesday....i dont think so shame there were small kids in the house.

man i cant believe it is a long weekend again this weekend...damn i was so looking forward to working this weekend but my staff told me this afternoon they want off...i suppose i will just have to go fishing or something...and its hunt the egg day on sunday...but more important remeber what it is really for

[daveob]

shame there were small kids in the house

yep, and threatening to stick them in the microwave isn't nearly as effective as a big pot of water on the stove.