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Option –09 True RMS AC
INTRODUCTION
809-1. INTRODUCTION
The True RMS AC option gives the 8842A the ability to make ac voltage and current measurements. The ac functions are selected with the front panel VAC and mA AC buttons, or by remote commands if the
809-2. INSTALLATION
The True RMS AC option is contained on a single,
WARNING
TO AVOID ELECTRIC SHOCK, DISCONNECT THE POWER
CORD AND TEST LEADS BEFORE REMOVING THE
INSTRUMENT CASE.
1.Remove the grounding screw from the bottom of the case and remove the two rear panel mounting screws (Figure
2.Holding the front panel, slide the case and rear bezel off of the chassis (Figure
3.Holding the True RMS AC PCA slightly above the chassis, component side down, connect the the ribbon cable from the True RMS AC PCA to the Main PCA and latch it in place. (See Figure
4.Connect the red lead from the True RMS AC PCA to stud W301 on the Main PCA. (See Figure
5.Make sure the heads of the four plastic latches are in the extended position. Guide the PCA into the 4 circuit board supports.
6.Fasten the True RMS AC PCA to the chassis by pressing the four nylon latches into the mounting supports on the chassis. (See Figure
7.Reinstall the cover and rear bezel on the chassis and attach the two rear panel mounting screws.
8.Attach the grounding screw to the bottom of the case.
WARNING
TO AVOID ELECTRIC SHOCK, ENSURE THE GROUNDING
SCREW IS FIRMLY ATTACHED TO THE CASE BOTTOM.
9.Calibrate the VAC voltage and mA AC functions according to the calibration instructions given in the Maintenance section.