GPS timing accuracy

[diegoarosio]

Hi,
just a simple question. I’ve searched through the forum and read the technical specs, but it is still not clear to me if the +/- 10ms (1 sample at 100sps) timing accuracy refers to both NTP and GPS timing.
Here [NTP and GPS timing details] it seems that timing error with GPS dongle plugged in is zero.
Can anyone get back to me on this point?
Thank you very much
Diego

[ivor]

hello diego,

i think the more complete explanation you are looking for is found in this post, as a reply to a similar question you had:

RS4D time synchronization

hello, to minimize the time difference between multiple shakes, the following: Minimize the difference between each Shake’s NTP daemon: arrange / set up a local NTP server that all the Shakes will connect to: 1.1. this should be on the same LAN as all the Shakes themselves connect a GPS unit to this NTP server: 2.1. make sure that the NTP daemon on this Shake is using the GPS module as the NTP server it is using to set its time configure all Shakes to use the NTP server set up in step 1 let…

we will look to getting this information included in the manual.

let us know if you have any further questions,
richard

[diegoarosio]

Hello Richard,
thanks for your reply.
I’ve already read the post you suggested. As far as I understand, when the time reference is given by GPS (and the unit is not connected to any NTP server) the timing accuracy is still 10ms, as you posted here [RS4D time synchronization - #8 by ivor].
This is due to the fact that the MCU clock of each unit has its very own drift. Is this correct?

Kind regards
Diego

[ivor]

hi diego,

yes, your understanding is correct,
richard