Güralp CMG-3ESP, Operator'S Manual

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CMG-3ESP Inside the 3ESP
The mass clamps will not secure the masses against hard knocks and jolts. The
3ESP should always be transported with at least 15 cm of foam padding. You will
have received suitable packing material with the instrument.
6.2.2 Automatic control
The 3ESP contains a control microprocessor which drives the centring adjustment
motors when its input line is grounded for 0.2 – 7 seconds. As an option, this
microprocessor can also be programmed to drive clamping motors, allowing you to
lock and unlock the masses remotely by grounding two further input lines. These
input lines can be controlled from the breakout box or Hand-held Control Unit.
Each command acts on the vertical, N/S and E/W masses in turn. The
microprocessor prevents the system from attempting incompatible actions (
e.g.
centring when the masses are clamped.)
While a command is taking place, if you are using a Hand-held Control Unit, its
BUSY LED will flash; you can use this for diagnostic purposes. See the description of
each command for full details.
When no command is active,
i.e.
all three lines are high, the control microprocessor
goes into a power-saving mode. In routine operation, the lines are controlled from
the breakout box, Hand-held Control Unit or digitizer. If you send control signals to
the 3ESP manually, you must ensure that the lines are pulled high after sending the
signal, or the equipment may be damaged. A “biased-OFF” type switch can be used
for this purpose.
6.2.2.1 LOCK (remote control option)
This command locks the masses and clamps the horizontal sensors by tilting them
up to their end stops.
If LOCK is activated when the masses are already locked, the processor will unlock
them and attempt to lock again. This is useful if you suspect that the locking
procedure has failed.
In detail, the process acts as shown in the following graph. The top three streams
are the
mass position outputs of each component (Z, N/S and E/W, respectively),
whilst the bottom one represents the state of the BUSY LED (up = on).
MAN-ESP-0001 31 Issue G - February 2016