Guralp Systems CMG-DM24 - Manual (Page 100)

CMG-DM24
To trigger an instrument from an external source through a relay:
•
Connect a the normally-open switch contacts of a suitable relay
between pins B and H, with the coil connected to your generator
so that pins B and H are connected when a trigger occurs.
•
The relay allows you to power the external generator from any
source. This includes the instrument's own power supply at
pins A and B, if it is suitable.
•
Connect the other pins as normal.
If you prefer, you can use a separate power source for your trigger
generator. However, because pin H is referenced to power ground, the
external power supply must share a common ground with that of the
digitizer, so you should connect the power supply ground to pin A.
100 Issue N