i3070series6_Site_Preparation+11-12.3.pdf.pdf - 第37页

Power Requirements 6 Site Preparation 6-5 Sizing the Input Wi re s and Circuit Breakers Ta b l e 6 - 1 shows the full-l oad amps (FLA) for each syst em type. Ta b l e 6 - 1 Power r equirements PDU Po we r Option Frequenc…

6-4 Site Preparation

6 Power Requirements

Power Drop

• A dedicated power drop must be provided for the system due to its high current

requirements.

• Copper wire must be used for the power drop.

• An electrician must determine the wire size for the power drop. The wires must

be sized to ensure that the voltage at the system does not drop below

90 percent of nominal (see Calculating the Minimum Voltage below).

Calculating the Minimum Voltage

The voltage at the system must be at least 90 percent of nominal. To calculate the

minimum rms voltage multiply the rms voltage by 0.9. To calculate the minimum

peak voltage, multiply the rms voltage by 0.9 and then 1.414. For example:

208 volts rms * 0.9 * 1.414 = 265 volts peak

Power Requirements 6

Site Preparation 6-5

Sizing the Input Wires and Circuit Breakers

Table 6-1 shows the full-load amps (FLA) for each system type.

Table 6-1 Power requirements

PDU

Power

Option

Frequency Voltage

line-to-neut /

line-to-line

Full-Load Amps (FLA) for:

E9905G E9903G/

E9902G

200–240V 3-Phase Delta 3PD 50/60 Hz 200

220

230

240

208–220V 3-Phase Wye 3PY 50/60 Hz 208

220

380–415V 3-Phase Wye

with Neutral

3PN 50/60 Hz 220 / 380

230 / 400

240 / 415

Neutral is not used by the systems for power options 3PD and

3PY. Neutral is shown in the diagrams because Neutral is

cabled into the PDU.

N (optional)

6-6 Site Preparation

6 Power Requirements

Basic Power Quality Survey

Power quality can affect system performance differently. The following procedure

is intended as a guideline and may not be the total solution. Failure to meet these

guidelines should serve as an indicator that a power quality consultant might be

needed to conduct a more in-depth power quality survey.

1 With the system operating, measure harmonic distortion at the system-input

connection. THD should be less than 5% and less than 3% for any single

harmonic.

2 With the system operating, measure the ground-to-neutral voltage at the

system-input connection; the voltage should be less than 4vp-p.

3 Turn the system power off and measure the line voltage at the system-input

connection; record this reading. Turn the system on and begin operating mode.

Measure the line voltage at the system-input connection again. The difference

between the two measurements should be less than 2%.

Other problematic power qualities include momentary voltage interruptions,

ground noise, and voltage spikes. A survey of these problems and others may

require the services of a power quality expert with specialized equipment.