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[CA] [CA11] EV-1 Sensor ROT Data
06-06-18, 11:15 AM
Post: #3
RE: [CA11] EV-1 Sensor ROT Data
Chuck,

Thank you for the details. It all makes complete sense that based on that level of accuracy (+/- 0.04° per second) the units will be displaying data that is changing fast if they are displaying degrees per minute from the degrees per second data. :-)

However, I don't think having the MFD display degrees per second is the right answer. I don't think the i70/i70S instruments and p70/p70S/p70R/p70RS control heads should display degrees per second either.

Based on all the information I have seen, it appears the rate of turn standard is degrees per minute. Example:
https://en.wikipedia.org/wiki/Rate_of_turn_indicator

Displaying degrees per second would be contrary to the established standard (if we can call it a standard).

I can see the benefit of faster data (degrees per second), but as we already know... if the MFD or other units are simply doing the math to convert to degrees per minute (degrees per second * 60 seconds), given the +/- 0.04° per second accuracy, then we can get +/- 2.4° as we are seeing, which is bad.

I see two options (maybe there are more):

Option 1. Have the MFDs and other units round the rate of turn per second data to the nearest 0.1° then do the math to convert to minutes for display purposes. This would take into account accuracy of +/- 0.04° "issue" and provide a more "stable" number.

If you think about it, even though you said the i70/i70S instruments and p70/p70S/p70R/p70RS heads are displaying degrees per second, they are only displaying to 1 decimal place (nearest 0.1), which is why we don't see the +/- 0.04° noise does not affect it.

Of course, this introduces the issue that the best you will ever display is 6° per minute.

Option 2. Have the EV-1 report in degrees per minute instead of degrees per second and have the displays (MFDs, and display heads) all display degrees per minute.

Doing this on the EV-1 would probably give more accurate data, and this has the benefit of having non-RayMarine equipment understand the data as per an established "Rate of Turn Per Minute" value.

Thanks again for the follow-up Chuck!
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[CA11] EV-1 Sensor ROT Data - rsqunit - 06-04-18, 01:18 AM
RE: [CA11] EV-1 Sensor ROT Data - rsqunit - 06-06-18 11:15 AM

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