Operating instructions

2-8 Overview
MB*/* Installation and Operation Manual
Figure 2-10 illustrates the location of the LO/HI voltage selector and the gas discharge tube surge
protector on the MPPS-II:
Figure 2-10
60/90 volt selector
460132-001
J1
TP1
TP2
R54
HI
LO
Voltage
selector
Gas discharge tube
or optional FTEC
You must remove the MPPS-II cover to access the selector illustrated in Figure 2-10.
Section 3, “Amplifier Setup” explains changing the setting of this selector to meet system
requirements.
The power supply includes a heavy-duty gas discharge tube which you can replace with the
optional fast-transfer electronic-crowbar (FTEC) surge protector. The FTEC fires at
approximately 245 V and presents a short circuit to the line during periods of overvoltage. After
the ac input voltage returns to normal, the FTEC resumes its open state.