Ac Power And Grounding Requirements - Toshiba Strata DK14 Installation And Maintenance Manual

DK40i Installation

AC Power and Grounding Requirements

AC Power and Grounding Requirements
The DK40i requires a solid earth ground for proper operation.
The AC power cord contains a conductor
for the "third-wire ground" provided by
the commercial power outlet. The third-
wire ground should be the only ground
necessary for the DK40i; this ground
must originate at the buildings main
power distribution panel and have a solid
connection to earth ground. (See
3-3.)
CAUTION!
AC Power and Third-wire Ground
Test
Test the "third-wire ground" for continuity by either measuring the resistance between the third
prong terminal (earth ground) and a metal cold water pipe (maximum: 1 ohm), or by using a
commercially available earth ground indicator. If neither procedure is possible, perform the
following earth ground test procedure.
WARNING! Hazardous voltages that may cause death or injury are exposed during
the following test. Use great care when working with AC power line
voltage.
➤ To perform the earth ground test procedure
1. Obtain a suitable voltmeter, and set it for a possible reading of up to 250VAC.
2. Connect the meter probes between the two main AC voltage terminals (white and black wires)
on the wall outlet. The reading obtained should be between 100~125VAC.
3. Move one of the meter probes to the third terminal (green wire ground). Either the same
reading or a reading of zero volts should be obtained.
4. If the reading is zero volts, leave one probe on the ground terminal and move the other probe
to the second voltage terminal.
CAUTION!
5. If a reading of zero volts on one terminal, and a reading of 100~125VAC on the other terminal
is obtained, remove both probes from the outlet.
3-4
Figure
Lack of proper ground
may cause improper
operation and, in extreme
cases, system failure.
If a reading of zero volts is obtained on both voltage terminals (white wire to
green wire, black wire to green wire), the outlet is not properly grounded. Omit
Steps 5 and 6, and see following CAUTION!
Third Wire
AC Ground
A
Electrical Building
Ground (Main Power
Distribution Box)
1.8 amps max.
Figure 3-3 DK40i Grounding Diagram
Ground 1 Third Wire Ground
To AC Power Cord
DK40i BaseKSU
Power
Supply
4' 5"
AC Voltage
115VAC
± 10VAC
FG
AC Current
4236
Alternate Ground
Grounding Rod
Strata DK I&M 5/99