Meyer Sound MPS-488HP Manual Do Utilizador

29

The power source for the 

MM-10ACX should always operate within the 

required voltage range, at least a few volts from the 
upper and lower ranges. This will ensure that AC volt-
age variations from the service entry — or peak volt-
age drops due to cable runs — will not cause the 
subwoofer’s amplifiers to cycle on and off or cause 
damage to the power supply.

The current draw for the MM-10ACX is dynamic and fluctu-
ates 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. The current rating is also used as a rat-
ing for slow-reacting thermal breakers. In addition, the 
Maximum Long-Term Continuous Current can be used to 
calculate the AC looping capability of the MM-10ACX.

■

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)

The Burst Current can also be used to calculate the AC 
looping capability of the MM-10ACX.

■

Ultimate Short-Term Peak Current — A rating for fast-
reacting magnetic breakers.

■

Inrush Current — The spike of initial current encoun-
tered when powering on.

You can use the following tables as a guide for selecting 
cable gauges and circuit breaker ratings for the system’s 
operating voltage.

The minimum electrical service amperage required by an 
MM-10ACX subwoofer system is the sum of the Maximum 
Long-Term Continuous Current for each unit. An additional 
30 percent above the minimum amperage is recommended 
to prevent peak voltage drops at the service entry.

For the 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.

Idle Current

0.21 A rms

0.20 A rms

0.23 A rms

Maximum Long-Term 
Continuous Current

0.48 A rms

0.31 A rms

0.55 A rms

Burst Current

1.1 A rms

0.6 A rms

1.3 A rms

Ultimate Short-Term 
Peak Current

2.2 A peak

1.6 A peak

2.5 A peak

Inrush Current

6.6 A peak

3.7 A peak

7.2 A peak

Idle Current

0.32 A rms

0.26 A rms

0.36 A rms

Maximum Long-Term 
Continuous Current

0.90 A rms

0.51 A rms

1.02 A rms

Burst Current

2.5 A rms

1.3 A rms

3.0 A rms

Ultimate Short-Term 
Peak Current

4.5 A peak

2.8 A peak

5.0 A peak

Inrush Current

7.6 A peak

4.4 A peak

8.4 A peak