WPI Biological Signals Amplifier, Инструкция по эксплуатации, Страница: 8 / 16

4 World Precision Instruments
Setting Up HG Pressure Amplifiers and Sensors
The HG amplifier and its sensor are
designed to measure the pressure of
the fluid perfusing a heart or an organ
(liver, kidney, mesentery), or the aortic
pressure developed by the left ventricle
of a heart in working mode. The second
pressure amplifier and sensor in the
system can be used with a catheter to
measure diastolic and systolic pressures
from the left ventricle of the heart.
Fig. 4—(Right) The HG Pressure amplifier,
front and back.
In addition to in-vitro applications,
like perfusion studies, the amplifiers
and pressure sensors attached to
catheters can be used to make in-vivo
measurements of blood pressures from arteries and veins in animals. If a pressure
sensor is going to be used:
1. Plug the connector on the end of the perfusion pressure sensor into the
IN1
9-pin Canon (D-sub) socket on the back panel of the amplifier. The sensor is
now connected to the HG1 amplifier module.
2. Plug the microphone jack of one of the output cables into the OUT1 socket of
the HG1 pressure amplifier. Connect the other end of the output cable to one of
the analog inputs of the data acquisition unit.
3. Before the transducer is connected to a perfusion cannula or catheter, check the
baseline level of the pressure recording channel. Turn the 4-way program switch
on the front panel of HG1 amplifier to
GND
. Turn ON the amplifier. A signal
of zero (0) volts is sent by the amplifier to the data recorder. If necessary, set
the baseline of the recording channel to zero (0) using the controls of the data
recording system.
4. Check the baseline output of the pressure amplifier. Turn the 4-way program
switch to MEAS . If the baseline of the pressure recording channel has shifted
above or below zero (0), adjust the position of the baseline seen on the
recording channel by turning the knob of the
BALANCE potentiometer on the
front panel of the HG1 amplifier until the baseline is set to zero (0), again.
5. Check the calibration of the pressure sensor and HG1 amplifier at either
10mmHg or 100mmHg. Turn the 4-way program switch to either 10(mmHg) or
100(mmHg) depending on the range of pressures being recorded. The voltage
change seen on the pressure recording channel should be 100mVDC for
10mmHg and 1VDC for 100mmHG.