51-0184-0100 EP08-06 MPA4-400R Anglès.doc 2 of 5
- Connect a load impedance formed by a 4
Ω
resistor shunted to a 1µ5F capacitor, and apply a
1KHz square waveform input signal. Using an oscilloscope, observe the output signal, at the
flat level areas of the squared waveform, only two or three ringing should be detected both at
positive and negative slope flanges. Increase the input signal level until the displayed signal
starts clipping. Check that, even when clipping, the ringing does not grow, and no more ringing
than before appear either.
- Verify the THERMAL protection circuitry. Short the unit’s
thermal probe pins Vs and Vout, and verify that the relay
releases, while the
THERMAL
indicator light up, as the
output signal is cutted off and the cooling fan increases its
speed until it reaches maximum airflow.
REMOTE CONTROL VERIFICATION
1-
Release all of the input circuit selection switches.
↑
.
2-
Attenuation potentiometers should all be turned up to their maximum level (right).
3-
Apply a 0dB 1kHz signal on channel 1 input.
4-
Check the output signal on channel 1’s output. Vo=41 Vrms.
5-
Connect the tool equipped with a potentiometer to REMOTE CONTROL CH1.
6-
Check the potentiometer sweep, its response curve and attenuation.
7-
Repeat this procedure on the rest of inputs and outputs, and on remote controls.
8-
When done, leave the REMOTE CONTROL configuration again OFF.
PROTECTIONS
- Signal generator OFF, 1V scale, select a 1kHz output signal and keep the level potentiometer
down to its minimum.
- Connect a 0.5
Ω
load impedance.
- Connect the oscilloscope to the module’s output.
- Switch on the generator and turn up slowly the output level potentiometer, while checking that
the output voltage keeps below these limits, as listed below:
FIRST EVALUATION POINT:
15Vpp (240V)
SECOND EVALUATION POINT:
18Vpp (210V)
Note: the signal clipping should appear without any distortion or ringing. Both evaluation points
are obtained by adjusting the variac’s output voltage.
- Repeat this process on all the other channels.
