EX12 USER’S GUIDE
P. 5
Voltage Requirements
The EX12 operates safely and without audio discon -
tinuity if the AC voltage stays within the operating win-
dow of
100V-120V
in 115V mode,
205V-240V
in 230V
mode and
225V-260V
when working in 250V mode,
at 50 or 60Hz.
CAUTION:
If the On LED does not illumi-
nate or the system does not respond to au-
dio input, remove AC power immediately. Verify that
the voltage is within the proper range. If the problem
persists, please contact KV2 Audio or an authorized
service center.
If the voltage drops below the low boundary of its safe
operating range, the loudspeaker will shut down if the
voltage does not rise above the low boundary before
storage circuits are depleted. How long the loudspeak-
er will continue to function during brownout depends on
the amount of voltage drop and the audio source level
during the drop.
If the voltage increases above the upper boundary of
the range, the power supply can be damaged.
NOTE
: It is recommended that the voltage
supply be within the rated voltage window.
This ensures that AC voltage variations from the
service entry—or peak voltage drops due to cable
runs—do not cause the amplifier to cycle on and off
or cause damage to the power supply.
NOTE:
For best performance, the AC cable
voltage drop should not exceed 10 volts, or 10
percent at 115 volts and 5 percent at 230 volts.
Make sure that even with the AC voltage drop, the
AC voltage always stays within recommended operat-
ing ranges. The minimum electrical service amperage
required by a EX12 speaker system is the sum of each
loudspeaker’s maximum continuous rms current. An
additional 50 percent above the minimum amperage
is recommended to prevent peak volt-age drops at the
service entry.
The Power Connector
The EX12 requires a grounded
outlet. It is very important that the loudspeaker AC sup-
ply be properly grounded in order to operate safely and
properly. Use the PowerCon AC cable-wiring diagram
on page 5 to create international or special-purpose
power connectors:
Current Requirements
Each EX12 requires approximately 5 Amps max at
115V AC for proper operation. This allows up to three
EX 12’s to be powered from one 15 A breaker at 115V
and up to 6 loudspeakers at 230V or 250V.
The EX12 presents a dynamic load to the AC mains,
which causes the amount of current to fluctuate de-
pending on quiet or loud operating levels. Since differ-
ent cables and circuit breakers heat up at varying rates,
it is essential to understand the types of current ratings
and how they correspond to circuit breaker and cable
specifications.
The maximum long-term continuous current is the
maximum rms current during a period of at least ten
seconds. It is used to calculate the temperature rise in
cables, in order to select a cable size and gauge that
conforms to electrical code standards. It is also used to
select the rating for slow-reacting thermal breakers.
The burst current is the maximum rms current during a
period of approximately one second, used to select the
rating of most magnetic breakers and to calculate the
peak voltage drop in long AC cables according to the
formula: V pk (drop)= I pk x R (cable total)
The ultimate short-term peak current is used to select
the rating of fast reacting magnetic breakers. Use the
table below as a guide when selecting cable gauge size
and circuit breaker ratings for your operating voltage.
CHAPTER 1: AC POWER REQUIREMENTS
Current Draw
115V Mode 230V, 250V
Max Long Term Continuous 5 A rms
2.5 A rms
Burst Current
7.5 A rms
5 A rms
Short Term Peak
20 A peak
10 A peak
Power connector assembly
