Scan bar flashing on HP Smart Tank 7006

[MOS_FET]

Why the scanner bar blinking even when in low power mode (or standby mode)? This would  reduce the life time of the scan led bar in long term!

In low power mode, no need to scan or no need for calibration! It is called by definition standby mode!

This would become in the future a design flaw.  Led bar on the scanner bar have limited life time, if you make them blink even short when being in low power mode will reduce their life time. What is the goal? Make the printer scanner led fail on the long term and either use the warranty to "force" your customer buy the replacement of the scanner bar or to buy a new printer?

Frankly, please uptdate the firwmware to stop this behaviour....!

Please don't propose to swicth off because your printer takes too much time to boot and please know when operated in USB, USB standard defines a suspend mode (eitherwise your are not compliant USB) where the device consumes 2.5mA at 5V which is equal to max consumption 12.5mW (it is very Hard to reach that), if you make blink scanner bar LED or even wifi blue  led active, you would not comply with USB suspend, therefore not compling with USB standard!

[Valsimot]

On the old scanners that used CCD and lamps had it, but the new CIS technology is more reliable in terms of lifetime expectancy. 

[MOS_FET]

Hello, thank for your reply and sorry to be straight forward.

Fortuntately technology is improving and led are more and more reliable! Sorry to say that I used CIS sensors back in 2008. It has become old technology now.

You are saying that it is more reliable but you gave no numbers.

How long reliable were old printer and how long is reliable HP smart Tank 7006 led (2 year, 5 year, 10 year etc..) and what about old printers please give same numbers. And for what usage intensity/ regularity/ pmw  cycle/do you lower their current? etc...

This is the only decent way with number to compare and not subjective comparison (=it is more, it is less, it is almost equal etc...).

Secondly let's suppose (it is only a supposition) it is more reliable but what is the need to switch ON LED bar on standby mode? If any calibration is required, it can be done while waking the printer, or on boot or just before the scan etc... So i don't see any technical reason or justificatiàn for this LED blinking...

By the way, you didn't answer my third question.  While on standby, Blue wifi Led indicator is switched ON (along with power indicator led) along with this pulsating led bar scan, i bet  this violates USB suspend max average current of 2.5mA of USB at 5V therefore violating USB standard. Is HP smart tank 7006 really eco friendly?

[Valsimot]

Sleep mode consumes 2W of power.

[MOS_FET]

 OK thanks for this information: 2W is far beyond superior to 2.5mA*5V= 0.0125mW.

And do  you have any technical explantion/requirement for the reason of making  blink the LED scanner BAR blink even in sleep mode?

[Valsimot]

The printer is powered with an internal power supply, not from a USB supply, so your calculation for USB suspend max average current/power doesn't apply in this case.

The scanner blinks in sleep for a faster wakeup to ready time, it's ready for scanning within seconds after waking up. The user doesn't need to wait for warm-up time and calibration time like in the old models.