Marantz MM7025, 5411 10586 001M manual Explanation of terms, Protection circuit, Speaker impedance

ENGLISH
Explanation of terms	Troubleshooting

P

Protection circuit

This is a function to prevent damage to components within the power supply when an abnormality such as an overload or excess voltage occurs for any reason.

In this unit, the STANDBY indicator and protection indicator blinks and the unit enters standby mode when an abnormality occurs.

S

Speaker impedance

This is certain-rated resistance of the speaker set to an alternating current and expressed in ohms.

The smaller the impedance, the greater the output.

However, load on the amplifier is increased. Use speakers whose impedance is supported by this unit.

If a problem should arise, first check the following:

1.Are the connections correct?

2.Is the set being operated as described in the user guide?

3.Are the other components operating properly?

If this unit does not operate properly, check the items listed in the table below. Should the problem persist, there may be a malfunction. In this case, disconnect the power immediately and contact your store of purchase.

Symptom	Cause/Solution	Page
The power does not switch on.	• Check that the power plug is inserted correctly in the wall socket.	7
Or, the power switches off immediately after	• The protective circuit has operated. In this case, remove the power plug	7, 10
being switched on.	from the wall socket, and wait for at least 1 minute before inserting it in the
	wall socket again.
There is no sound from the speakers.	• Check the speaker connections and connections to the other devices.	6
	• Alter the input selector to match the input connector (BALANCED or	4
	UNBALANCED) of the connected device.
The power suddenly switches off during use,	• The internal temperature of the unit has increased, causing the protective	–
and the STANDBY indicator and protection	circuit to operate. Remove the power plug from the wall socket, wait until
indicator flash at approximately 0.5 second	the temperature of the unit has dropped adequately, and then insert the
intervals.	power plug back into the wall socket.
	• Install this unit in a well-ventilated location.	–
	• Use speakers that have the specified impedance.	4
	• If the two core wires of the speaker cables are touching, or if a core wire	4, 10
	is out of the terminal causing the core wire to touch the rear panel of this
	unit, the protective circuit will operate. Remove the power plug from the
	wall socket, and firmly re-insert the core wire, or fix the terminal before
	reconnecting it.	–
	• Turn the volume down on the amp connected to this unit, and insert the
	power plug again.
When the power switches off suddenly	• The protective circuit has operated. In this case, remove the power plug	6, 7, 10
during use, the STANDBY indicator flash	from the wall socket, re-examine the installation conditions of this unit, and
at approximately 0.1 second intervals and	check the speaker cable connections. If the same situation occurs when the
protection indicator flash at approximately 0.5	power is switched on again, contact the Marantz Service Center.
second intervals.

10