Hello, there!

Just to make sure you don't delete me from the Forum, here is another little question!!! I have an accelerometer connected to DT800 as a bridge. When displayed on CHART as a graph, the output shows 3 sec Heart Beat spikes (-ve). Is that normal?

Should this accel be connected as a Voltage i/p??? For info - The bridge Sense input is 10 V and looking at the cct of the accel, the two outputs from the bridge are connected to something looking like an OpAmp. ------ added this later!!!!

Actually, having used another accelerometer, with just a bridge config and connected as a bridge BGV to DT800, I can see the same regular spikes (about 3 sec freq) when looking at the output in CHART. Is that normal?

Chris

Good afternoon fredflinstone,

I've not seen this before, how large are these heart beats?
What do you have the accel attached to?

Cheers,
Roger

I will have to connect the system and recheck. This will unfortunately be in several weeks. Another job, in the meantime! Will be in touch, then.

But, from memory these -ve spikes only showed when the accel was connected as a bridge. Not large. When accel connected as Voltage and power supply taken from 10 v sensor power, these spikes disappeared. So, it must be something to do with the bridge connection vs the accel internal cct.

Anyway, the system is working and just was curious about these 3 sec - since it seems to be the same as the DT "heart beat"!

Chris

Good afternoon Chris,

Have you tried connecting the - sig to the DT800 ac terminal?
This will give it a ground reference.

Cheers,
Roger