Hud for a Classic Inspo

Mark Chase

Question, Is it possible to hang on all three cells? i am not a lecy person but it seems unlikely.

The URI HUD has three cells three sets of wires and 6 LEDs a red and a green for each cell. So if one cell loom became compromised, you have two left and ALL the LED are independent so you have one LED fail and the others keep on working.

If it hangs? it would have to hang all three so it must be an error in the controller as you have three sets of circuitry monitoring three cells and flashing 6 LED's. If your using a flashing system what stops that hanging in a given set point and flashing carrying on?

Also if you have an LED failure don't you loose the data for all three cells? On the Uri HUD the loss of an LED only looses you a single green or a red on one cell. So the others still works and warns you about hi / low on that cell.

When I lost a red LED on the HUD (easily identified on boot up) I still had the green warning me about set point. If i lost the green Id still have the red flashing below 0.7 and above 1.5 so not perfect but not at least it warns of a serious cell issue.


ATB

Mark Chase

__________________
Is it supposed to make that noise ?

I took my unit to the dive shop and demanded they bolt on every thing that would fit.

Join my elite diving teem and get a Tshirt

"Doing It Chasey"Hammerhead Eccr Advanced Diving System

Sutty

Another vote for Uri's HUD. As I see it the "hung" idea is not an issue as it uses 3 independant circuits (except for battery) so you would have to hang all 3 simultaneously - highly unlikely. Like Mark I like the solid green=all well approach, you do react fast to a flash if its not there all the time.

The biggest difference to my mind is that with Uri's system you have a redundant signalling system with independant circuits tracking all 3 cells, giving you enough information to stay on the loop at setpoint if your main display fails. This is why Uri calls it a primary HUD.

The only real weak point to my mind is the original unit's electronics - theoretically if the rebreather electronics are sufficiently flooded to short out the outputs from the O2 cells then the HUD (any HUD working off the same cells as main displays) will have no reliable signal to work from. This is an advantage of the Kiss displays too, where the 3 displays are independant.

The way my HUD is wired into my Kiss does mean that the HUD is dependant on a Fischer connector plugging the cells to the HUD unit. This means the HUD is dependant on a single O-ring seal in the Fischer - however if the connector floods (cos I didn't do it up fully!) it is pretty obvious that the HUD signals are not making any sense - and the original displays keep working because of some very simple protective circuitry within the head.

Neil

__________________
Never forget that life is a finite resource.