Grounding; Power Line Transients; Power Consumption Of 4072/4073 System Instruments - Agilent Technologies 4072A Advanced Pre-Installation Manual

Site Preparation
Electrical Requirements

Grounding

The system cabinet, the system controller, and all computer peripherals are grounded through the three-wire power
cable grounding wire. Earth grounding protects the operator against shock hazards and protects the system
components against catastrophic events, such as lightning.
Also, all system components must have a common ground reference that is electrically isolated from any
non-system equipment owing to the interfaces between the system controller, system instruments, and computer
peripherals. Otherwise, signals generated by non-system equipment could cause system errors.
WARNING
To protect operators from electric shock injury due to current leakage, a grounding
connection is essential before connecting the power supply. When you connect the system to
the power supply, connect the grounding wire before connecting other power wires.
The 208/220/240 V line voltage option does not contain a ground-fault circuit interrupter (GFCI). If you plan to
AC
include GFCI in your power lines, select a breaker that has a rated sensitivity of 30 mA for the 208/220/240 V
line voltage option. This ensures that the breaker is not tripped by regular current leakage. For the 200 V
voltage option, the PDU is equipped with a GFCI as a main circuit breaker.

Power line transients

Heavy electrical loads from nearby machinery or equipment, for example, elevators or electric welders, can cause
intermittent system errors, even if that equipment is on a different circuit breaker. To prevent this, you must provide
a separate, completely independent circuit with isolated ground and circuit breaker coming directly from the main
power source of the building.
NOTE
Agilent Technologies does not recommend installing printers or plotters close to the 4072/4073
tester. When the electrical motors in these peripherals begin operating and their electric
consumption increases, noise from the print head or pen movement may cause system errors.

Power consumption of 4072/4073 system instruments

Table 2-4 lists the actual power consumption for each component in the 4072/4073 tester. The total power
consumption can be calculated from the table. For example, in the case of a system with 208 V
where the system controller (HP c8000), 17 inch flat-panel display, testhead power supply, 4284A precision LCR
meter, and 3458A digital multimeter are included in the system cabinet and the power for these instruments is
supplied from the cabinet PDU, the total power consumption results in 7.8 A. If you add three 81110A pulse
generators in the system cabinet, the total power consumption results in 12.3 A. Note that there is a margin of 11.7
A (= 24.0 − 12.3). If you add another instrument consuming 2.0 A, you can connect its power cable to the cabinet
PDU. The total current consumption must be less than the maximum current for instrument or controller power
outlets.
Table 2-3 shows the number of installable unit. If you are using only the 81110As in the system cabinet, up to five
81110As can be mounted. You can have up to two 8114As. In the case of one 8114A, you can mount up to four
81110As, and in the case of two 8114As, you can mount up to two 81110As or E4411B. It is very important that the
maximum number of 81110As or 8114As installed in the system cabinet and the power consumption of these
instruments not be exceeded.
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Agilent 4072/4073 Preinstallation Guide, Edition 4
AC
line
AC
line voltage,
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Chapter 2