Toner Coverage (Average, %)

[iMind]

	Quote:			Originally Posted by zyqwiz
	Went to switch on SP5-056 on our own MPC4500 and it was already on! Doesn't show anything though.

He said SP5061-001 displays icon on LCD.

[zyqwiz]

	Quote:			Originally Posted by iMind
	He said SP5061-001 displays icon on LCD.

I know what SP5-061 does - I'm talking about the 2 people that mentioned SP5-056 to display coverage.

[Daniel Jokinen]

I use SP 8851 - 8881 to find out how many copies were made within each coverage percentage, then input them in Excel and calculate an average. Works every time!

[mrwho]

Could we take a look at that excel formula of yours?

[Jan Sommer]

no need for excel and stuff^^

use the data of 8-921, here's the example for black:

	Quote:
	SP8921-1 : SP8921-14 = average coverage per page

so it's basicly just:

	Quote:
	(coverage color "x" total) : (pages color "x" total) = average coverage per page

[Daniel Jokinen]

Oh sorry I didn't see the reply...
The formula I use is as follows:

The number of pages for the first coverage range * coverage (see example 1) + number of pages for the second coverage range * coverage + next and so on. Divide the sum with the sum of total number of pages, that gives you a "high" average.

Example 1

This is what the machine log displays:
Coverage 0-2%: 5000 pages
Coverage 3-5%: 15000 pages
Coverage 6-10%: 6000 pages
Coverage 11-20%: 2000 pages
Coverage 21- < : 1000 pages

(5000 * 2 = 10000) + (15000 * 5 = 75000) + (6000 * 10 = 60000) + (2000 * 20 = 40000) + (1000 * 21 = 21000) = 206000

206000 / total of 29000 pages = 7,10%


Now 7,10% is pretty high since we're using the highest percentage in the range, i.e. 6000 * 10 instead of 6, 7, 8 or 9 which is in the same range. This is a worst-case-scenario number. To bring justice into the equation, you need to calculate the lowest possible number as well, which then becomes example 2:

(5000 * 1 = 5000) + (15000 * 3 = 45000) + (6000 * 6 = 36000) + (2000 * 11 = 22000) + (1000 * 21 = 21000) = 129000

129000 / total of 29000 pages = 4,45%.
Then add the two numbers together (7,10 + 4,45 = 11,55) and divide in 2 and you've got yourself 5,775% coverage, which is probably pretty close to the truth.

Hope that's mathematic enough for ya

[mrwho]

/me head hurts

Okay, I took note of that. Thanks a lot!

[Jan Sommer]

like I said - it doesn't need to be that sketchy and complicated - just take a look at sp 8-921

you can calculate all values with your cellphone calculator within 2 minutes even if you dropped school after the third grade

[Daniel Jokinen]

	Quote:			Originally Posted by Jan Sommer
	like I said - it doesn't need to be that sketchy and complicated - just take a look at sp 8-921 you can calculate all values with your cellphone calculator within 2 minutes even if you dropped school after the third grade

I've seen that too, but never trust a machine to do a mans job No really, there are actually 3 ways of doing this to be precise. Your way, 8-921, but also 8-601 and mine, 8-861. The results vary a little though, this is an example from our showroom MPC2800:


BK Y M C
8-921 4,34% 4,54% 5,28% 7,85%
8-601 3,70% COLOR=23,23%
8-861 4,43% 4,69% 5,41% 7,05%


It seems your way and mine are fairly close to each other Jan Yours might even be even more precise, I must admit, because of the way the machine counts. Rather than within a range like in my example, it shows a total. Great!

So everyone knows it - Use 8-921 for average toner coverage. Divide the sum of the total percentage with the number of pages for that color and you're done! Thanks Jan!

[Jan Sommer]

cheers

at first I've tried to calculate this more complicated as well