Meyer Sound MPS-488HP - Manual (Page 13)

MPS-488HP OPERATING INSTRUCTIONS
13
MPS-488HP CURRENT DRAW
The current draw for the MPS-488HP and its connected
loudspeakers is dynamic and fluctuates as operating levels
change. Since different cables and circuit breakers heat up
at varying rates, it is important to understand the following
types of current ratings and how they affect circuit breaker
and cable specifications.
■ Idle Current — The maximum rms current during idle
periods.
■ Maximum Long-Term Continuous Current — The
maximum rms current during a period of at least 10 sec-
onds. The Maximum Long-Term Continuous Current is
used to calculate temperature increases for cables, to
ensure that cable sizes and gauges conform to electrical
code standards. This current rating is also used as a rat-
ing for slow-reacting thermal breakers.
■ Burst Current — The maximum rms current during a
period of around one second. The Burst Current is used
as a rating for magnetic breakers. It is also used for cal-
culating the peak voltage drop in long AC cable runs
according to the following formula:
V pk (drop) = I pk x R (cable total)
■ Ultimate Short-Term Peak Current — A rating for fast-
reacting magnetic breakers.
■ Inrush Current — The spike of initial current encoun-
tered when powering on.
For current draw values for the MPS-488HP with connected
loudspeakers, see Appendix C, “MPS-488HP Specifica-
tions.”
The minimum electrical service amperage required by an
MPS-488HP is the sum of the Maximum Long-Term Contin-
uous Current for all loudspeakers connected to the
MPS-488HP. An additional 30 percent above the minimum
amperage is recommended to prevent peak voltage drops at
the service entry.
NOTE: For best performance, the AC cable
voltage drop should not exceed 10 V, or
10 percent at 115 V and 5 percent at 230 V. Make
sure that even with AC voltage drops that the AC
voltage always remains within the operating window.
SAFETY ISSUES
Pay close attention to these important electrical and safety
issues.
■ The MPS-488HP requires a grounded outlet.
■ Do not use a ground-lifting adapter or cut the AC cable
ground pin.
■ Keep all liquids away from the MPS-488HP to avoid haz-
ards from electrical shock.
■ Do not operate the unit if the power cables are frayed or
broken.
Earth ground
Chassis ground