Connectors for outdoor model for vault use


We have a solar-powered seismic station with a broadband sensor and we’d like to add a couple of Raspberry Boom and Share instruments into the same vault to run side by side.
We are running off of a big 12 V battery that is recharged by solar and I’d like to run Raspberry instruments from the same source.

I already got a couple of step-down DC-DC at 5 VDC converters rated at 20W with constant output that I plan to power those boxes with. Can you please let me know what are the models of the external connectors used on those boxes for power and ethernet so that I can wire things nicely?

This seems to be the connector type that would work:

Also is there a way to add external GPS unit for that setup. I see that there is a GPS sold on the website for around $200 with USB interface. Is that a GPS or just GPS antenna (it seems to me that it is a full GPS with an integrated antenna and USB interface to power it up and send data).

Thanks a lot,

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Hello seismicMonitor,

It’s quite the installation! When you have set up the Shakes, could I ask you for some pictures (naturally, if possible) so that the entire community can see it? In-the-field setups are always interesting.

The connectors are classified as M12, just like the one you linked to me. To complete the wiring information, I’ll attach the following images that describe both the LAN and power couplings in detail:

Powersource IP67

And, regarding your last query, you’re again correct. What we sell in our shop is a complete GPS with an integrated antenna and a USB connection so that the only requirement is to connect it to one of the Pi USB ports, and the Shake will be ready to go for off-the-grid installations.

If you have any other questions, I remain available.

Thanks a lot for confirming the connector and GPS information and I will be happy to provide some pictures of our installation as we make progress towards installing it in the field in the next couple of weeks.

No good deed goes unpunished so I have a few more technical questions for you:

  1. Regarding the GPS I would like to know which baud rate is required to communicate with the RaspPi and if it works with full NMEA datastream.

  2. Do we need to change any internal settings in order to let it know that the time signal should be derived from GPS?

  3. When I was working with GPS’ as an accurate time reference a PPS signal from GPS was used to set the start of the second very accurately. Do you use PPS in this case or just rely on the NEMA stream to synch accurate time?

  4. Is there a portable GPS NTP time server that we can use for this application since I plan to use both RS4D and RS&BOOM in the same location?

How about something in the link below:

  1. Should we run the tube from the pressure transducer on BOOM to the outside of the vault?

  2. What hardware do you recommend for the metal base for the instruments in order to level and lock it in place?

  3. Since in this application instruments are powered from a big 12V battery (100 Ahr) that is recharged via solar panel and solar charge regulator, the solar regulator is configured to disconnect loads if battery voltage bets below around 11.5 Volts and then is turned back on when battery voltage goes back above 12.5 V. Is there a way to protect RS instruments and issues a shutdown command as monitor devices senses alow battery voltage instead of shutting them cold.

  4. Along similar lines what would be the safest way to turn the devices back on when the battery level is back to a normal level? Both power questions are applicable to us since we’d also like to run the RS instruments purely on an external battery to collect some ambient noise data while the battery has enough charge (again another device could monitor battery voltage levels and issue commands over IP to RS)

Thanks a lot for your time and sorry if some of these questions were already been answered. But I hope that this tread could be a good resource for the community.


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Hello seismicMonitor; no problem! I’m here to help everyone on RaspberryShake-related matters. Also, apologies for the delay, as I was collecting information to offer you the most complete answers.

I’ll answer following your pointed list so that there is no confusion:

  1. You can find information on our receivers (models included) here: GPS Antenna

  2. No, as our Shake OS will automatically detect a connected GPS, starting to communicate with it for timing details. You can find more information here: NTP and GPS timing details

  3. We use PPS to deliver the most accurate timing data to our Shakes.

  4. This is a bit more complex, but it’s a situation we have encountered. You could use the item you have linked (you’ll have to do all the necessary testing and integration yourself), or you could do the following:

The question with a single GPS connected to multiple Shakes is always to maintain synchronized and correct timing between all Shakes. As you are working with multiple instruments, I would recommend synchronising the various devices’ timing via a single PC server. We have some documentation here on our manual, on the dedicated NTP page: NTP and GPS timing details — Instructions on Setting Up Your Raspberry Shake

The computer running the local NTP server can be any computer whatsoever: a regular PC, a laptop, or even another Raspberry Pi.

The basic idea behind this is that you have a local computer that has two things:

  • a connected GPS device (or a constant internet connection) that governs the hardware clock on this computer
  • running an NTP server (not the client daemon) to which a Shake Pi will connect to use as its NTP server

In this way, you will have a single NTP server that will regulate the timing of all the connected devices instead of having multiple NTP connections for each device. This will give you an improved level of accuracy, ensuring that all your devices are in synchro with each other, and all their data can be promptly used together without the need to check for the aforementioned synchronization.

  1. Yes, that would be the best practice, especially if the vault is airtight. Ensure that the connecting tube is free of kinks or sharp bends that will affect the pressure detection of the infrasound sensor. You can find more details on our dedicated page here: Raspberry Boom (RBOOM/ RS&BOOM) Infrasound Monitors

  2. You can have something very simple to lock the Shakes in place after levelling them via the provided screws. I would recommend a solution similar to the one implemented by one of our users, described here: DIY Guide For A Home Raspberry Shake Vault - Raspberry Shake in the Securing the Raspberry Shake section.

  3. As there is no way of precisely reading the input voltage of the Pi board, you have a couple of options to address this. It may be possible with the vcgencmd python package (vcgencmd) as one user has done something similar in the last post of this thread: Using under voltage warning for pi shutdown - Raspberry Pi Forums , but you will have to experiment.

As an alternative, executing this from the command line

sudo zgrep -a -i voltage /var/log/syslog*

will provide all the lines in the log files where voltage issues have occurred, such as undervoltage events too. You can monitor the logs with this, inside a script, and trigger a soft shutdown when a voltage line appears, making the Shake turn off safely.

If, instead, you want the solution to be completely external to the Shake itself, you will need some hardware (voltage monitor, a relay, and such) paired with software to handle the shutdown. You can utilize the unused GPIO pins (details here: Technical Specifications) to connect the various equipment you will be employing to achieve the desired result.

  1. Similar to my previous answer, if you want to keep everything external, you will need some microcontroller (that you could already have available), like an Arduino board, for example, that constantly monitors the battery output voltage and then activates a script to send a signal via relay to the RaspberryShake to turn on again. You could also implement a hysteresis mechanism to prevent frequent on/off switching when the battery voltage is around the threshold, and make sure that whatever monitoring equipment you’ll be using is isolated from the Shake to prevent any damage.

For both these two points, I reiterate, you will have to experiment with various tests to determine the best solution for your installations.

I hope that these answers have provided what you were looking for. Again, if you require anything else, I remain available.

I designed a custom Pi HAT, FYI that monitors the (solar-source) battery supply and gracefully shuts down and restarts the Shake’s Raspberry Pi in the event that the batteries get too depleted. This prevents data corruption when the Pi is otherwise running under voltage. This was created to solve this very problem that was occurring on the Shake I was using which is solar powered. You can message me if you would like to purchase one.