Bus Volts and Left and Right Alternator Ammeters using DAC

Analogue Bus Volts and Left and Right Alternator Ammeters

Updated (sept 29, 2007): 

Because the initial meters (100 mA) did not work I (after very long search) found other meters. I changed the faceplates (see result below)

The gauges are located in the lower left side of the lower panel, see picture below (with the initial meters)

Because we had not enough space to put the bus volts ammeter under the alt load ammeters, we put the bus volt right from the alt ammeters.

Above: detail picture of real positioning of the Bus Volts and Left and Right Alternator Ammeters;

Meter Scale

- Bus voltage scale: 0 - 30 Volts
- Alt Load : 0 - 100 Units (% of max load)

Concept

We use an analogue gauge to make these Bus Volts and Left and Right Alternator Ammeters. A DAC (Digital to Analogue converter)  will convert 5 bits per gauge; each bit is an output from the Opencockpits mastercard. The resolution will be 2^5 (= 32 steps). So for three gauges I'll use 3 x 5= 15 bits = 15 outputs of the mastercard. The calculation and control of the bits will be done by SIOC.

bus volts ammeter

The range for the scale for the bus volts is 0 to 30 Volts; 
so e.g. with a 3 bit DAC, each step would be 30/8=3,75 Volt on the output scale

We use a 5-bit DAC (2^5=32) so each step is approx 1 Volts on the output scale of the bus volts ammeter.

alt load ammeters

The range for the scale for the Alternator Ammeters is 100 units  on the output scale

We use a 5-bit DAC (2^5=32) so each step is approx 3 Units on the output scale of the Alternator Ammeters.

For more info about the Digital to Analogue converter follow this link

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Technical Design of the gauges

Send mail to info@baron58 dot com  with questions or comments about this web site.