Valleylab Force FX-8C, Service Manual

Page: 116 / 218

Calibrating the Generator
5-32 Force FX-8C Service Manual
3.
Check and adjust the I factor for the Blend mode.
a.
Press the Blend button.
b.
Press the footswitch cut pedal and check the voltmeter for a
reading equivalent to 1000 ± 8 mA rms.
c.
Stop activation. If the output current reading was too high, raise
the I factor by pressing the Coag up arrow (
∆
) button. If the reading
was too low, lower the I factor by pressing the Coag down
arrow (
∇
) button.
Repeat this step until the voltmeter reading is within the stated range.
4.
Disconnect the test cables and remove the 10 ohm resistor.
5.
To save the current sense gain calibration and go to the next calibration
step, press the Bipolar up arrow (
∆
) button.
Next, check the voltage sense gain factor as described in Step 6 – Check and
Adjust the Voltage Sense Gain.
Step 6 – Check and Adjust the Voltage Sense Gain
Equipment required:
• Two short test cables (less than 61 cm [24 in.] long) with banana plugs
• Current transformer (such as the Pearson Model 411 or equivalent)
• True RMS voltmeter (such as the Fluke 8920 or equivalent)
• 1000, 2000, and 3000 ohm noninductive power resistors (such as the
Dale NH-250)
• Bipolar footswitch and monopolar footswitch.
Verify that the Bipolar display shows calibration step 6. The Cut and Coag
displays show the V (output voltage) factor. If it is four or more digits, the
most significant digits are in the Cut display.
Notice
Do not adjust the voltage sense gain while the generator is activated.