14
Phase Check
(for Electricians Only)
When you have made all of the terminal strip connections (and installed the external batteries if the UPS has
them), complete this phase check. You will need an AC voltmeter.
1.
Make sure the main circuit breaker in the load service panel is off, or make sure the loads cannot receive
power from the UPS.
2.
Make sure the bypass switch is in the "OFF" position.
3.
At the UPS AC input service panel, turn on the input power to the UPS and the bypass switch.
4.
Next, turn the AC Disconnect switch on. The AC LINE light on the UPS will light.
If your UPS does not have a separate battery cabinet, follow Section 305 on page 11.
5.
Turn the B610 On/Off switch on. (See Section 400 on page 20.)
6.
Turn the bypass switch to "UPS."
7.
Make sure the voltage from the UPS to the loads is close to the voltage from AC line to the bypass
switch. (There may be slight differences.)
•Find the measurement points for your bypass switch type (internal or external) and model on
the next page.
•Use an AC voltmeter to measure the voltage between these points on the terminal strip. (See
the terminal strip label.)
•Record the voltage measurements for your bypass switch in the spaces provided below.
BPE-02, 04, or - 05:
AC from UPS Output
AC Line Input
7 to 8 ________ VAC
11 to 12 _______ VAC
6 to 7 ________ VAC
10 to 11 _______ VAC
6 to 8 ________ VAC
10 to 12 _______ VAC
The voltages written in the first column should be similar to the voltages in the second column.
(They may be slightly different.) If voltages are more than a few volts apart, check the terminal
strip connections and correct any wiring problems. If you need help, call Best Power's
Worldwide Service or your local Best Power office.
Important:
If the AC Input voltage is 208 volts, you will normally measure 104 volts AC between
the following AC output terminals:
External Bypass Switches:
(6 and 7) and (6 and 8)
Do not connect any 120-volt load to the 104-volt terminals.
CAUTION
Before changing the bypass switch from OFF to UPS or AC Line, check for correct operation by following
the steps below. To prevent damage to the loads (protected equipment), make sure the main circuit breaker
in the load service panel is OFF, or make sure the loads cannot receive power from the UPS.
