E250P/P12SW subwoofers
SAFETY INFORMATION
Warning
Any person performing service of this unit will be exposed to hazardous voltages and the risk of electric shock. It is assumed that any person who removes the amplifier from this cabinet has been properly trained in protecting against avoidable injury and shock. Therefore, any service procedures are to be performed by qualified service personal ONLY!
Caution
Early revisions of the unit did not have a power switch. Hazardous voltages are resent within the unit whenever it is plugged in.
Before amplifier is plugged in, be sure its rated voltage corresponds to the voltage of the AC power source to be used. Incorrect voltage could cause damage to the amplifier when the AC power cord is plugged in. Do not exceed rated voltage by more than 10%: operation below 90% of rated voltage will cause poor performance or may shut the unit off.
Leakage/Resistance Check
Before returning the unit to the customer, perform a leakage or resistance test as follows:
Leakage Current. Note there is no power switch on early revisions of this unit. When the power plug is plugged in, the unit is live. Connect the unit to its rated power source. Using an ammeter, measure the current between the neutral side of the AC supply and chassis ground of the unit under test. If leakage current exceeds 0.5mA, the unit is defective. Reverse the polarity of the AC supply and repeat.
Resistance. Measure the resistance from either side of the line cord to chassis ground, If it is less than 500k ohms, the unit is defective.
WARNING! DO NOT return the unit to the customer if it fails one of these tests until the problem is located and corrected.
Critical Components
All components identified with the IEC symbol in the parts list and schematic diagram designate components in which safety can be of special significance when replacing identified with. Use only the
replacement parts designated in the parts list or parts with the same rating of resistance, wattage or voltage.
List of Safety Components
Requiring Exact Replacements
Part Number/ | Description | |
Designator |
| |
|
| |
F1 | Line Fuse Slo Blo 2.0A | |
5x20mm | ||
250V UL approved | ||
| better with polarized plug, UL | |
| approved wired with the hot side | |
| to fused | |
| side. Use with factory | |
| replacement panel strain relief | |
| (70305) only. | |
|
| |
PT1 | Power Transformer. | |
Use only factory | ||
replacement. | ||
| ||
|
| |
BR1 | Bridge diode. Use only | |
factory replacement. | ||
| 3300uF 80V electrolytic | |
| filter caps. Be sure | |
| replacement part is at | |
C6,8 | least the same working | |
voltage and capacitance | ||
rating. Also the lead | ||
| spacing is important. | |
| Incorrect spacing may | |
| cause premature failure | |
| due to internal cabinet | |
| pressure and vibration. | |
|
| |
| Rear Amp Cover | |
Use only factory | ||
| replacement | |
Inductor | L1 - Use only factory | |
replacement | ||
Inductor | L2 - Use only factory | |
replacement | ||
Inductor | L3 - Use only factory | |
replacement | ||
Inductor | L4 - Use only factory | |
replacement | ||
|
|
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