How is ink level determined?

[PalaDolphin]

I have a noobie question for my Pro-100: How does the printer driver determine the ink level to report Estimated Ink Levels in the Ink Details dialog box under the Maintenance tab? So, I just learned about the prism at the bottom of the cartridge which determines if the reservoir is empty. And I've noticed that it accurately reports low ink right before empty; I don't know if low can also be determined using the prism or through calculation/estimate.

 

[apetitphoto]

My take on it is that the driver talks to the printer about ink levels. The printer uses a very sophisticated estimation method that I would call "informed guessing." Given that the printer knows the capacity of the cartridges and it knows when it uses a color, it just subtracts from the full ink quantity when it fires that color. This new quantity becomes the new known ink level that is recorded on the chip. The mirror sensor is a fail safe.
So it's okay to fill a cartridge without resetting it, but dangerous to reset a cartridge without filling it.

 

[PalaDolphin]

That's what I figured. I've gotten into a routine of resetting the chip just before inserting the needle. Thanks @apetitphoto for the info.

 

[Drjim]

Cleaned and dry cli42 are 13.6 gm. My full, new ones are 27.4 gm. So that's about 13.8 ml of ink. If 1/2 the ink is in the reservoir (I haven't measures that yet) the sensor would detect 1/2 full. The low indication would be counted down from there. I'll try to remember to weigh at that point.

 

[PalaDolphin]

Referring to my notes, my filled cartridges range from 32.10 gm to 32.72 gm. That's probably why they spilled out when I opened them just before installing. I'd say I over filled. Live and learn.

 

[Drjim]

The data I'm trying to collect is the weight just as the reservoir goes empty and the weight when the printer says "low".

BTW - was 32+ gm with the orange clip on? Seems like you couldn't overfill by 5 ml.

 

[The Hat]

How does the printer driver determine the ink level to report

There is no connection between the printer and the cartridge at first, when you install a new cart, the printer then expects it to be a full cart, the Light sensor will check it’s the correct cart and the chip is full, (Unused) and this information is stored in the memory for that chip.

The printer will ignore the cart till the light sensor can see the prism inside and then you get a low ink warning, this is the time that the printer takes control and counts every ink drops it fires out and it will then tell you when to replace the now empty cart.

The cart is never fully empty, because there is a bit of redundancy built in to insure you don’t ruin your print head, and if you happen to top off a cart before the low ink warning, the printer can still remember when the cart/chip was installed and will cause an out of ink warning by memory, while ignoring the inactivity of prism.

The printer memory doesn’t have to be very accrete but it’s still never wrong, one or two drops eider way won’t make any difference because it’s got the extra 1 or 2 ml to play with...

 

[PalaDolphin]

BTW - was 32+ gm with the orange clip on? Seems like you couldn't overfill by 5 ml.

32.10 gm w/o the orange clip.

 

[Roy Sletcher]

The data I'm trying to collect is the weight just as the reservoir goes empty and the weight when the printer says "low".

BTW - was 32+ gm with the orange clip on? Seems like you couldn't overfill by 5 ml.

THis could be complicated because you are weighing the cart+ink in the sponge and the result could be distorted by differing sponge retention rates.

My sponges when new. IE freshly purged, and refilled seem to have more sponge content, than older cartridges that have been refilled many times.

This assessment is based on the fact the fresh ly cleaned and refilled sponges have a darker hue same as the ink in the chamber. After many refills sponge seems to be depleted and never quite reache the same intense hue as the newer refill. I am interpreting this colour shift to be due to less sponge content. To be certain would have to weigh the carts at the various stages of sponge usage.

Just a theory at this stage.

rs

 

[stratman]

The printer will ignore the cart till the light sensor can see the prism inside and then you get a low ink warning, this is the time that the printer takes control and counts every ink drops it fires out

Recalling the tests done with blocking the prism sensor and what happened to the ink level warnings -- the ink counting still occurred. It has been claimed that the prism is used to adjust the ink counting for improved accuracy, not as the trigger for the chip to begin counting ink use.

Were all the warnings displayed? I do not recall.