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UPS disturbance of seismometer

A project log for Single-cell Li-Ion Powered UPS for Raspberry Pi

A simple yet complete UPS solution for most Raspberry Pi embedded applications, using a single-cell Li-Ion Battery.

bud-bennettBud Bennett 07/01/2017 at 15:120 Comments

It doesn't appear that the seismometer is disturbed by the UPS. Today I disconnected the wall wart supplying power to the seismometer, waited about 5 minutes and then reconnected it. Here's the plot from the seismometer:

Yes...it seems like there is a problem, but apparently the problem is with me. The two major "bumps" in the data are caused by my proximity to the seismometer since I had to get down on my knees within 2 feet of the seismometer in order to unplug the wall wart. 100 counts on the seismometer ADC is equivalent to about 32 nano-meters of displacement to the concrete slab that it sits on. I repeated the experiment -- this time I only kneeled down next to the seismometer without disconnecting the wall wart. Here's what the seismometer reported:

The first trace shows very little difference (that I can determine) in the section that was running off the UPS power. I'm satisfied. Now I must wait for a power outage to see how the UPS performs for a longer period.

Just for grins and giggles, here's what a "real" earthquake looks like, from last week's magnitude 6.8 quake down in Guatemala:

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