permanence of the connection at the earth ground point. Tools required: • T10
Torx driver. • 5/16 inch hex wrench for N6700A mainframes. • 3/8 inch hex
wrench ...
Agilent Series N6700 - Operation at 400 Hz Please attach or keep this sheet with the Agilent N6700 User’s Guide.
Power Factor The Agilent Series N6700 can be operated at 400 Hz input line frequency. All specifications apply when operating at 400 Hz, however, the power factor of the unit is affected as follows: •
Under full load at 400 Hz, power factor drops from ~1.00 (@120 VAC) to ~0.76 (@ 265 VAC).
•
Power factor will also degrade under light or no load conditions, both at 400 Hz and at 50/60 Hz.
Redundant Ground Requirement At 400 Hz operation, the leakage current of the unit exceeds 3.5 mA. This requires the installation of a redundant ground from the instrument chassis to earth ground. This ensures that ground is still connected during a single fault condition, and that leakage current will be diverted to ground. The redundant ground must be permanently attached (requiring a tool to remove) to the unit as well as to the earth ground point. The following procedure only describes how to make the permanent connection at the unit. The user must ensure the integrity and permanence of the connection at the earth ground point. Tools required: •
T10 Torx driver
•
5/16 inch hex wrench for N6700A mainframes
•
3/8 inch hex wrench for N6700B mainframes
Customer-supplied hardware required: •
Ground wire (14/16 AWG)
•
Uninsulated ring terminal for attaching wire to unit Tyco p/n 34122 or equivalent for N6700A mainframes Tyco p/n 34124 or equivalent for N6700B mainframes
•
Hardware for attaching wire to earth ground point
Redundant Ground Installation WARNING
SHOCK HAZARD. FAN HAZARD. Turn off the mainframe and disconnect its power cord before attempting any of the following procedures.
CAUTION
Observe all standard electrostatic discharge precautions before starting this procedure.
Step 1. Remove the blower cover. Remove three screws from the top of the cover and two screws on the sides. Tilt the cover up and slide it out.
Step 2. Remove the top cover of the GPIB board. Remove the three screws along side the unit. Remove the screw at the end of the cover that attaches the cover to the pc board.
Step 3. Remove the binding post (1) from the rear of the chassis. 3
2
1
Step 4. Crimp the appropriate ring terminal (2) onto the end of the ground wire. Step 5. Place the ring terminal onto the threaded end of the binding post. Reinstall the binding post on the chassis with the washer and nut (3). Step 6. Rotate the ring terminal so that the ground wire does not interfere with any other connectors on the back of the unit. Tighten the binding post to the chassis. Torque for N6700A mainframes = 15 – 20 in-lb. Torque for N6700B mainframes = 20 – 25 in-lb. Step 7. Reassemble the mainframe. Step 8. Attach the 400 Hz label to the top of the unit. Place the label above the existing label that is closest to the AC input connector.
