Inter-Tel AXXESS Manual page 265

F. REPLACE THE ORIGINAL POWER SUPPLY UNIT, IF NECESSARY
HIGH VOLTAGE. When the system power is turned on, the power supply unit contains
110VAC. Before inserting or removing the power supply unit, make sure that the AC
POWER switch has been turned OFF for at least five minutes. Failure to allow the high volt-
age to dissipate can cause bodily injury.
8.7 If the power supply is defective, replace the unit as follows (see
lowing page):
Remove the four screws securing the panel on the front of the equipment chassis and set
1.
the panel aside.
Turn OFF the system AC POWER switch and wait at least five minutes.
2.
Disconnect the AC power cable and the ground wire from the front of the power supply
3.
unit.
Remove the four screws securing the panel on the top of the equipment chassis and set
4.
the panel aside.
Disconnect the backplane-to-power supply interface cable from connector J11 on the
5.
chassis backplane.
Remove the three screws securing the power supply unit to the top of the chassis card-
6.
file (see
Lift the power supply unit up out of the chassis and set it aside.
7.
Insert the new power supply unit and replace the three screws.
8.
Connect the new backplane-to-power supply interface cable to connector J11 on the
9.
chassis backplane.
Replace the top panel on the chassis.
10.
Connect the AC power cable and the ground wire to the front of the new power supply
11.
unit.
Remove all the circuit cards from the chassis, then perform the power supply electrical
12.
test as outlined on
Ensure that the power supply unit is properly grounded by performing one of the fol-
13.
lowing tests:
NOTE:
Replace the Original Power Supply Unit, if Necessary
INTER-TEL
Figure 3-39 on the next page).
page 3-83.
The power supply must be properly tested and grounded to prevent possible system
damage.
•
Use a digital multimeter to measure the difference of potential between the chassis
ground point and the power neutral, and between the chassis ground point and the
third wire ground. If the voltage measurement exceeds 0.5V, noise may develop
on the system. If this occurs, call an electrician.
•
Use a Megger to test the ground point. (A Megger should be available through the
local power company.) The reading should be 5 ohms or less.
For additional information on grounding requirements, see
® ®
AXXESS MANUAL VERSION 11.0 – May 2008
CAUTION
CAUTION
Installation
Figure 3-39 on the fol-
page 3-81.
Page 3-79
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