AMETEK SFA Series - Manual (Page 56)

Verification and Calibration Sorensen SFA Series
4.3.1 C URRENT M ODE
1. Set the SFA Series unit to operate in remote current programming
mode using an external 0-5 Vdc voltage source as shown in Figure 3–6
in Section 3.3 Remote Current Programming.
2. Attach a precision meter across the shunt Kelvin terminals.
3. Attach a precision meter in parallel with the voltage programming
source.
4. Set the voltage source to 0.0V ± 1mV.
5. Apply AC power and verify the current mode indicator is illuminated.
6. Verify that the unit is set to 0A ± 0.8% of full-scale output. If necessary,
adjust R47 for zero current through the shunt (see Figure 4-1 in Section
4.1.2 Preparation).
7. Set the programming voltage to 5.0V ± 1mV.
8. Verify that the unit is set to 100% ± 0.8% of full scale output current. If
necessary, adjust R33 for 100% of full scale current on the shunt.
9. Set the programming source for 0.5V
±
1mV.
10. Verify that the unit is set to 10% ± 0.8% of full scale output current. If
necessary, adjust R47 for 10% of full scale current on the shunt.
11. Repeat the steps above as required to obtain the required accuracy.
12. Set the programming source to obtain 100% output current on the
shunt. Verify that the front panel meter displays 100% ± 1% of full-
scale output current. If necessary adjust R85 such that the current
display reads 100% current.
CAUTION!
Hazardous voltages may be present on the output after the output is disabled.
Allow 5 minutes to drain any charge to safe levels before connecting or removing
output wiring.
4-4 M550292-01 Rev G