Guralp Systems Limited
MAN-T60-0005 - CMG-6TC Operators' Guide

Chapter 4. Configuring the response mode

The CMG-6TC is available in two versions. Each version has a set of four different frequency response modes, from which the operator can choose. The four response modes are referred to as SP (short period), SMP (short-medium period), LMP (long-medium period) and LP (long period).

Response Mode

Build Version A pass-band

Build Version B pass-band

SP

1 second to 100 Hz*

1 second to 100 Hz*

SMP

10 seconds to 100 Hz*

30 seconds to 100 Hz*

LMP

30 seconds to 100 Hz*

60 seconds to 100 Hz*

LP

60 seconds to 100 Hz*

120 seconds to 100 Hz*

* Versions with 50Hz low-pass corners are also available.

The response mode can be changed at any time using either of the following methods:

In order to use the first method (serial console menu), connector pins S and T should be left open circuit (not connected).

In order to use the second method (connector pins), the serial console menu should first be used to set the response mode to “LP” (option 0).

4.1 Setting the response mode using the serial console

To configure the 6TC response mode using the serial console menu, follow the instructions given in section 5. Note that pins S and T on the connector should be left open circuit when relying on the menu to set the response mode.

4.2 Setting the response mode using the connector pins

Note: Refer to Appendix A on page 13 for information on connector pin-outs.

In order to set the response mode using the connector pins, the serial menu should first be used to set the response mode to “LP” (option 0). If any other mode is selected via the serial menu, only that mode and “SP” mode can be enabled using the connector pins.

Response mode

Pin configuration

Pin S

Pin T

SP

Connect to pin Y

Connect to pin Y

SMP

Leave unconnected

Connect to pin Y

LMP

Connect to pin Y

Leave unconnected

LP

Leave unconnected

Leave unconnected

Note: If a mode other than “LP” has been selected using the serial console menu, it is still possible to select “SP” mode using the connector pins by connecting both pin S and pin T to pin Y.