METRON QA-45, Руководство пользователя и обслуживания, Страница: 44 / 74

TP8 - TP6 +8.8V ±
0.2V
TP8 - TP4 -8.0V ±
0.3V
TP8 - TP2 +2.5V ±
0.075V
TP8 - TP5 -8V +2 -1V
TP8 - TP3 +5V ±
0.1V
5. Connect the frequency counter to TP7 and read the frequency.
Requirement: 2 MHz (
±
0.002 MHz).
6. Slowly reduce the voltage from the power supply until the in-
stant the display gives the message: 'Change battery, and reset
system'. Measure the operating voltage with the multimeter.
Requirement: 6.9V (
±
0.3v). Return the operating voltage to
9.0V. and reset QA-45 by switching off the power for a short
period.
7. Select 80 BPM in the ECG Wave Menu. Connect the oscillo-
scope to TP1 for signal, and TP8 to ground. Check that QA-45
generates a 80 BPM signal with an amplitude of approximately
250 mV on the R pulse. Connect the oscilloscope to the High
Level ECG contact and check that the same signal is present,
only with an amplitude of approximately 1V on the R pulse.
8. Set power to OFF. Measure the resistance from the RL output to
the RA, LA and LL outputs.
Requirement: 1000 ohm (
±
30 ohm).
9. Measure the resistance from the RL output to the V2, V3, V4,
V5 and V6 outputs.
Requirement: 1000 ohm (
±
30 ohm).
10. Set power to ON and go into the SYSTEM TEST (F1) of the
page 3 menu and choose ECG + by moving the cursor and
pressing SELECT (F4) . Measure and adjust the voltage be-
tween TP1 and TP8 to 0.490V
±
1 mV. Choose ECG 0 from
menu. Measure the voltage between TP1 and TP8 and check
that it is b20 mV and -10 mV.
11. Choose ECG + from the System Test Menu, measure the volt-
ages between the ECG outputs, and check that they fall within
the limits shown in the following table:
Contact Power limit Nom. Value Upper limit
RL - RA 1.20 mV 1.35 mV 1.50 mV
RL - LA 2.40 mV 2.65 mV 2.90 mV
RL - LL 3.00 mV 3.35 mV 3.70 mV
RL - V1 2.70 mV 3.02 mV 3.30 mV
RL - V2 3.30 mV 3.72 mV 4.10 mV
RL -V3 4.00 mV 4.49 mV 5.00 mV
RL - V4 4.50 mV 5.06 mV 5.60 mV
RL- V5 4.00 mV 4.49 mV 5.00 mV
RL - V6 3.30 mV 3.72 mV 4.10 mV
12. Measure the voltage at the High ECG output.
Requirement: 2.0V (
±
0.05v).
2