Activity hdfirmware/firmware

1:40 pm

Michael Garthwaite

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HD-DEN-15306-1
resumed reviewing

11:59 am

jtaylor (deleted user)

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Re: HD-DEN-15306-1
replied to Sean Nash

The root cause is that abnormal AC power loss on the HD causes abnormal operating conditions and spurious errors. The valves return to position after the alarm is cleared, not when AC returns. The ...

The root cause is that abnormal AC power loss on the HD causes abnormal operating conditions and spurious errors. The valves return to position after the alarm is cleared, not when AC returns. The timer gives a ten-second window following removing the power fail signal and the alarm condition, where the alarm block is active. The original block used the alarms alone, we changed to the CPLD power loss detection - which returns with the return of AC. Clearing the alarms late means removing the block before the valves return to normal operation.

I think there are two approaches. We already have distributed failsafe that is entered on power fail, which we recover from after the alarm is cleared.
1. Create a pervasive state that affects every operating mode, allowing transitions to "safe" states during alarms, then back to the original operating state. The safe state would not register errors until after the transition back to normal operation.
2. Block errors until both AC is returned and the alarm is cleared when normal operation is restored.

The second approach is much simpler and addresses the root problem: odd control configurations resulting from having alarms with conflicting controls. In this case, the secondary alarms are spurious since they result from the valves dropping into a safe position, for instance, on the loss of AC. We also have a handful of other errors that occur under these conditions, fan speed, for instance, as well as valve positions,

11:57 am

jtaylor (deleted user)

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Re: HD-DEN-15306-1
replied to Sean Nash

Added alarm 62 detection disable as suggested.

10:02 am

Dara Navaei

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HD-DEN-15396-2
started review

HD-DEN-15396_2 Alarm 42 HD Fault Dpo Rotor Encountered IN Blood Prime Dvt 00

2:44 pm

Dara Navaei

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HD-DEN-15396-1
Closed

2:14 pm

Dara Navaei and Sean Nash

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HD-DEN-15396-1
finished reviewing

1:48 pm

Dara Navaei

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HD-DEN-15396-1
started review

HD-DEN-15396_Alarm 42 HD Fault Dpo Rotor Encountered IN Blood Prime Dvt 001 2

6:03 pm

Dara Navaei

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HD-DEN-15375-1
Closed

6:02 pm

Sean Nash

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HD-DEN-15375-1
resumed reviewing

4:46 pm

Dara Navaei

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HD-DEN-15375-1
started review

HD-DEN-15375_FW Dialysate Heating Fixes

10:01 am

Dara Navaei

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HD-DEN-15250-1
started review

HD-DEN-15250_Pre Treatment Does Not End Successfully

9:59 am

Sean Nash

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Re: HD-DEN-15306-1
commented on review

This doesn't seem like a fix to root cause - may not work if user clears alarm quickly. Suggest looking at valve driver where alarm 62 is detected/triggered and maybe zeroing positionOutOfRangeCoun...

This doesn't seem like a fix to root cause - may not work if user clears alarm quickly.
Suggest looking at valve driver where alarm 62 is detected/triggered and maybe zeroing positionOutOfRangeCounter (reset 1 sec persistence) if AC power is out. That way, when AC is restored, valves will have a whole second to get where they're supposed to be before alarm is triggered.

8:55 am