Pyramid T-1 User Manual page 27

T1 Hall Probe System
The voltage can be monitored by a voltmeter or oscilloscope. The monitor output is not affected
by the Ethernet communications or by other programs running on the client computers. It will in
fact continue to track the measured field even if the Ethernet is disconnected.
This example shows the T1 measuring a 21 Hz magnetic field waveform with 25 kHz sampling
with the monitor output connected to an oscilloscope.
NOTE
The monitor output is created by the T-1 processor, which allows it to use the calibration
parameters to achieve good accuracy. The output voltage is adjusted each time the T-1 makes a
reading. If you are using a low sample rate and the field is changing you will see the resulting
steps in the monitor voltage.
TIP
Use a high sampling rate if you want a good display of fast changing magnetic field on an
oscilloscope or digitizer connected to the monitor output.
11.3 Monitor mode: PID
The PID mode allows the T-1 to act as a servo controller for electromagnets. This allows the
magnet to be commanded to a specific exact field value, as measured by the T-1 probe. The
accuracy and stability of the field setting is limited only by the accuracy, precision and stability
of the field reading. Effects such as power supply drift and magnet hysteresis can be eliminated.
The monitor output is used by the servo controller software to control the current of the power
supply to maintain the requested field value. The power supply must have an interface which
allows its output current to be controlled by an analog voltage.
CAUTION
T1 User Guide T1_UG_210314 Page 27 of 42