OpenPlotter project

[conachair]

Originally Posted by manitu

I was talking about Original and aftermarket outboard sensors . But glueing a BMP180 to the head could work, I guess. Any digital solution on the water pressure?

.Manitu

Water pressure I've never even thought about so can't help there I'm afraid, but for head temp the ds18n20 sensors are the way forward, I haven't connected one to openplotter on a Pi yet but the page is there ready so should be plug and play. Also not sure about display options yet though signalK might come of age any day now if we're lucky.
As for the numbers the senors spit out, this was recorded on an arduino with a sensor on the head and another on the exhaust loop.



With one of these just zip tied to the head/exhaust.

[Sailoog]

Originally Posted by Saqqara

Hi Sailoog, has the specific hardware been selected for the upcoming SPI ADC?

I basically thought of using simple and cheap MCP3008 ADC (10 bits) or MCP3208 (12 bits). These chips have 8 inputs and a SPI interface to communicate with the processor. For instance we could have:

- 2 inputs for 2 battery banks sensors.
- 2 inputs for aux power source (solar panel, wind generator) sensors.
- 4 extra inputs (engine rpm, wind sensors...)

For voltage and current monitoring I would like to know your opinions about limits, I mean, max values of voltage and current that the divider should support.

V: 15 max? (solar panels can reach 22V in sunny day but there is always a stabilizer between panels and battery, isn't it?)

A: 180A max? (the problem here is the windlass which can be really hungry)

How about these dividers https://www.sparkfun.com/products/10644? they support up to 180A. The problem could be that they are designed to measure from 0 to 50V and we would measure from 0 to 15 and that would mean a loss of accuracy.

[Sailoog]

Originally Posted by misterjenkins

I've been playing around with open plotter, in the first instance, I'm hoping to use it to decode AIS signals and send them to an android tablet running OpenCPN.

I've got everything installed, I've calibrated the receiver, but I never seem to get any signals (I'm about 500yds from a marina, and Marine Traffic shows signals there).

From the NMEA inspector, I can see the following status messages when I restart NMEA:
Failed to connect with localhost: 101101.Error: 111, trying to reconnect

This is then replaced by the message

Failed to connect with localhost: 101101.Error: Timed out, waiting for data...

Can anyone help with this?

Thanks

openplotter version?

antenna?

DVB-T receiver model?

calibration value (ppm)?

[Sailoog]

Manitu, look at this...

https://bitbucket.org/R_P_Ryan/enginemonitor/wiki/Home

The EngineMonitor is an Arduino-based system for older marine diesel engines. It provides diagnostic information that is typically found only on modern engines....

Lots of good and inspiring ideas.

[affinite]

Originally Posted by Sailoog

I basically thought of using simple and cheap MCP3008 ADC (10 bits) or MCP3208 (12 bits). These chips have 8 inputs and a SPI interface to communicate with the processor. For instance we could have:

- 2 inputs for 2 battery banks sensors.
- 2 inputs for aux power source (solar panel, wind generator) sensors.
- 4 extra inputs (engine rpm, wind sensors...)

For voltage and current monitoring I would like to know your opinions about limits, I mean, max values of voltage and current that the divider should support.

V: 15 max? (solar panels can reach 22V in sunny day but there is always a stabilizer between panels and battery, isn't it?)

A: 180A max? (the problem here is the windlass which can be really hungry)

How about these dividers https://www.sparkfun.com/products/10644? they support up to 180A. The problem could be that they are designed to measure from 0 to 50V and we would measure from 0 to 15 and that would mean a loss of accuracy.

Comments:
Some boats are 24v
Some boats have 3 battery banks (I have 3 (Bow Thruster, House, Start)
The NASA commercial battery monitor shunts are 200A and 100A. I have a 200A

Questions
Will you provide a facility to read tank level sensors?
I would particularly like to read my 0-190 ohm fuel sender
A fresh water sender would be nice too.
Is the ability to read and display multiple DS18B20 temp sensors in the pipeline?

[Davidasailor]

Originally Posted by Sailoog

I basically thought of using simple and cheap MCP3008 ADC (10 bits) or MCP3208 (12 bits). These chips have 8 inputs and a SPI interface to communicate with the processor. For instance we could have:

- 2 inputs for 2 battery banks sensors.
- 2 inputs for aux power source (solar panel, wind generator) sensors.
- 4 extra inputs (engine rpm, wind sensors...)

For voltage and current monitoring I would like to know your opinions about limits, I mean, max values of voltage and current that the divider should support.

V: 15 max? (solar panels can reach 22V in sunny day but there is always a stabilizer between panels and battery, isn't it?)

A: 180A max? (the problem here is the windlass which can be really hungry)

How about these dividers https://www.sparkfun.com/products/10644? they support up to 180A. The problem could be that they are designed to measure from 0 to 50V and we would measure from 0 to 15 and that would mean a loss of accuracy.

I use an MCP3008 on a pi for monitoring our boat. Currently I just use 2 channels on it - main bank voltage and bilge pump voltage (goes high when the pump cycles). Our boat has a VDO panel with a bunch of inputs that I plan on tying into to get more info. That would add 2 other battery banks, and voltage levels from each of 3 water/fuel tank sensors. Our boat also has a 50mV/100A max shunt that the VDO panel reads to show amperage. I know all of the house loads go through that shunt, but I'm not sure about the windlass. I'd like to tie into the leads from that shunt to record amperage on the pi, but I'll need a higher gain ADC to get something useful out of the 50mV shunt range.


Sent from my iPhone using Cruisers Sailing Forum

[muttnik]

Originally Posted by conachair

Water pressure I've never even thought about so can't help there I'm afraid, but for head temp the ds18n20 sensors are the way forward

The problem with jumping back in to a thread on the last page after missing a few is that you can misinterpret.

First thought: Don't think I need to know water pressure in the heads but knowing the temperature there would be pretty useful in helping answer the "do I really want to get up?" question.

Not so relevant in Sailoog's part of the world. More so for winter liveaboards nearer conachair or me.

[manitu]

Originally Posted by muttnik

The problem with jumping back in to a thread on the last page after missing a few is that you can misinterpret.

First thought: Don't think I need to know water pressure in the heads but knowing the temperature there would be pretty useful in helping answer the "do I really want to get up?" question.

Not so relevant in Sailoog's part of the world. More so for winter liveaboards nearer conachair or me.

Water pressure alarm is a must-have when running surface propeller and tuned 2-strokes.
It signals a broken impeller, broken/bent pickup, or broken water hose before you seize the engine. The water temp indication is to slow ,if you dont cach in at once it starts climbing.

Cylinder temp, water pressure, volts and rpm. Those are the basics on older 2-stroke engines.

.manitu

[manitu]

Sorry if this has been asked before , but, in a full scale system with radar , can openplotter change the UDP packets from the radar to TCP, so it can be transmitted to wireless devices?


Edit: temperature in the heads.. haha , finally caught it.

.manitu

[muttnik]

Originally Posted by manitu

can openplotter change the UDP packets from the radar to TCP, so it can be transmitted to wireless devices?

Let me pre-empt any reply by Sailoog by asking...

Are you sure that's what you want?

OpenCPN's radar plugins (unless they've changed since last I looked: do correct me if they have) and proprietary display programs associated with radar units which use udp multicast won't know anything about making a TCP connection.

The elegant and seamless way (though not scalable but we don't care in this use case) to bridge multicast radar/sonar packets onto wireless would be layer 2 multicast-to-unicast: The bridge does igmp snooping on the wireless interface and sends L3 multicast traffic via L2 unicast to only those stations from which it has seen a join of the relevant group.

Some googling throws up evidence that OpenWRT has recently acquired the ability to do this but I'm unaware of such ability in the general Linux kernel so wouldn't be optimistic that OpenPlotter could do this.

Of course I could be completely wrong and welcome anyone putting me right :-)

[Sailoog]

Originally Posted by affinite

Questions
Will you provide a facility to read tank level sensors?
I would particularly like to read my 0-190 ohm fuel sender
A fresh water sender would be nice too.
Is the ability to read and display multiple DS18B20 temp sensors in the pipeline?

Now OP can read a float switch and warn of an empty/ful tank. No level measure. That should be measured by analog sensors.

I am not familiarized with senders. Do they output a variable voltage to read? or do you have to read a variable resistor value?

On OP v0.6.0 will be implemented the ability of read just one DS18B20 but multiple DS18B20 is the next in the TO DO list.

[Sailoog]

Really useful info about voltage and current onboard, thanks!

I am afraid there are a lot of possible sensors, infinite combination of then and too many magnitudes to measure. Instead of choosing magnitudes to apply to the SPI interface of OP (bank 1, bank 2, tank level, water pressure ...), It will be better to design some open system to customize it, I mean...

There are 8 total possible analog inputs. When you define an analog input in OP, you will set:

• The channel (1-8)
• The name of the magnitude to measure (voltage battery bank 1/2/3, engine rpm, water pressure ...)
• The unit of the magnitude (Volts, Amp, rpm)
• The value obtained at that moment with a reliable measurement system in order to have calibration data.

Once created, the magnitude and the measured values would be present in the triggers/actions system and optionally in the NMEA stream.

Each sensor installation should be responsible for getting the correct voltage to the ADC.

What am I forgetting?

[Sailoog]

Originally Posted by manitu

Sorry if this has been asked before , but, in a full scale system with radar , can openplotter change the UDP packets from the radar to TCP, so it can be transmitted to wireless devices?

The only thing that OP could get from UDP, multiplex and send to TCP is NMEA 0183 and I assume you are talking about other kind of data, aren't you?

[Davidasailor]

Originally Posted by Sailoog

Really useful info about voltage and current onboard, thanks!

I am afraid there are a lot of possible sensors, infinite combination of then and too many magnitudes to measure. Instead of choosing magnitudes to apply to the SPI interface of OP (bank 1, bank 2, tank level, water pressure ...), It will be better to design some open system to customize it, I mean...

There are 8 total possible analog inputs. When you define an analog input in OP, you will set:

• The channel (1-8)
• The name of the magnitude to measure (voltage battery bank 1/2/3, engine rpm, water pressure ...)
• The unit of the magnitude (Volts, Amp, rpm)
• The value obtained at that moment with a reliable measurement system in order to have calibration data.

Once created, the magnitude and the measured values would be present in the triggers/actions system and optionally in the NMEA stream.

Each sensor installation should be responsible for getting the correct voltage to the ADC.

What am I forgetting?

You might also want to make a customizable refresh rate for each channel. Some channels like RPMs might need to be fast refresh, whereas things like tank sensors could probably suffice at a reading per minute or so.


Sent from my iPhone using Cruisers Sailing Forum

[affinite]

Originally Posted by Sailoog

Now OP can read a float switch and warn of an empty/ful tank. No level measure. That should be measured by analog sensors.

I am not familiarized with senders. Do they output a variable voltage to read? or do you have to read a variable resistor value?

On OP v0.6.0 will be implemented the ability of read just one DS18B20 but multiple DS18B20 is the next in the TO DO list.

S.
Most basic fuel senders simply present a variable resistance eg 0-190 Ohm. If you are taking OP down the MCP3008 ADC path then I will setup and monitor a simple voltage divider incorporating the fuel sender.
Regards