## PSN-L Email List Message

Subject: Re: EV-17 wiring?
From: ChrisAtUpw@.......
Date: Mon, 28 Jan 2002 17:17:48 EST

```Dear Dave Saum,

The data sheets for the EV-17 vertical can still be found at
http://www.bc.edu/bc_org/avp/cas/wesobs/seismometers/ev17.pdf

The 'standard' coil resistances are 500 and 5000 Ohm. The 0.7 critical
damping resistors are 1,300 or 13,000 Ohm. The wiring connections are not
given, but the sheet claims 'Use of a standard ETL P14A plug-in connector
facilitates quick cable and damping resistor changes when desired'. The photo
shows a single connector with a Y jointed lead, suggesting that at least two
connections are required.

Are they in insulated pairs? One pair may be a calibration coil. Could
the other one be a temperature sensor? What are the resistances? Does the
output of the 5 K coil change when you put say 1 mA through another pair?
Give the case a tap and see if the 5 K output is damped and if the other
connectors give any signal at all.

Regards,

Chris Chapman
Dear Dave Saum,

The data sheets for the EV-17 vertical can still be found at http://www.bc.edu/bc_org/
avp/cas/wesobs/seismometers/ev17.pdf

The 'standard' coil resistances are 500 and 5000 Ohm. The 0.7 critical damping resisto
rs are 1,300 or 13,000 Ohm. The wiring connections are not given, but the sheet claims 'Use of a standard ETL P14A plug-in conn
ector facilitates quick cable and damping resistor changes when desired'. The photo shows a single connector with a Y jointed l
ead, suggesting that at least two connections are required.

Are they in insulated pairs? One pair may be a calibration coil. Could the other one b
e a temperature sensor? What are the resistances? Does the output of the 5 K coil change when you put say 1 mA through another
pair? Give the case a tap and see if the 5 K output is damped and if the other connectors give any signal at all.

Regards,

Chris Chapman
```