PROTECTION MODES

Basic Operation

Lexicon

PROTECTION MODES

The CX amplifiers are equipped to protect against overheating and miswiring, as well as electrical failures such as short circuits, device failures, internal faults, and DC output to the speakers.

THERMAL PROTECTION

The amplifier includes thermal protection for each channel, the main power transformer, and chassis. If a heatsink temperature exceeds 95˚C, the channel will deactivate and the corresponding channel status LED will flash blue. When the heatsink cools to normal operating temperature, the channel will automatically reac- tivate and the corresponding channel status LED will return to constant blue.

If the amplifier chassis exceeds a temperature of 58˚C, the amplifi- er will shut down all channels and all the channel status LEDs will flash blue. When the chassis cools to normal operating tempera- ture, all of the channels will automatically reactivate and the chan- nel status LEDs will return to steady blue.

If the main power transformer temperature exceeds 100˚C, the transformer will deactivate, all channel status LEDs will no longer be lit, and the red standby LED will flash rapidly. Once the trans- former has cooled, it will automatically be reset and the amplifier will operate normally. The channel status LEDs will return to constant blue, and the red standby LED will no longer be lit.

CURRENT PROTECTION

The CX amplifiers use a combination of voltage and current infor- mation to protect the output transistors. The amount of current capable of being delivered to the load is dependent on how much voltage appears across the output transistors. Inversely, this means that the more output voltage available, the more current capabili- ty available, which translates into higher power output.

In addition to the voltage and current thermal protection, the CX amplifiers have a time dependent instantaneous current limit. The amplifier is capable of delivering 20 amps peak into a load for a short duration of time.

DC PROTECTION

Each channel includes DC protection to prevent DC and frequen- cies below 10Hz from reaching the speakers. If this protection activates, the output relay will open and the corresponding front panel channel status LED will flash blue. After approximately 4-sec- onds, DC protection will be automatically deactivated. The relay will close and the corresponding channel status LED will return to constant blue. If DC or frequencies below 10Hz are still present, DC protection will be automatically reactivated. The amplifier will continue to engage this protection until the problem is no longer present.

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Lexicon CX-5, CX-7 manual Protection Modes, Thermal Protection, Current Protection, Dc Protection, Basic Operation, Lexicon

FAQ

What are the main protection modes of the Lexicon CX amplifiers?

The main protection modes are thermal protection, current protection, and DC protection, designed to safeguard against overheating, miswiring, and electrical failures.

How does the thermal protection work?

The amplifier includes thermal protection for each channel, the main power transformer, and chassis. If a heatsink temperature exceeds 95C, the channel will deactivate and the corresponding channel status LED will flash blue.

What is DC protection?

DC protection is designed to prevent DC and frequencies below 10Hz from reaching the speakers. If this protection activates, the output relay will open and the corresponding front panel channel status LED will flash blue.