LC ZAPpulse Predator Power Supply

Predator 2 Power Supply Unit for ZAPpulse Modules

The Predator 2 PSU is a complete power supply module developed especially for the ZAPpulse 800XE amplifier modules (or the ZAPpulse 2.3 series); it can also be used as a general purpose power supply. The module contains both the normal ±60V DC supply and also the external Gate Driver supply, which enables you to reduce heat emission from the amplifier to an absolute minimum. If you do not use the external Gate Driver supply, the ZAPpulse modules will generate a Gate Drive voltage from the -60V rail. However this is obviously at expense of some power loss of around 6 Watts per ZAPpulse module. This heat loss can be almost completely avoided by using the Gate Drive supply of the Predator 2 power unit. However is does require the mains transformer to have a 15V AC winding for this purpose.

There are two different versions of the Predator Power Supply Unit. The standard version has 2x 10,000uF capacitance at 63 Volts and is meant for amplifiers of 200 Watts per channel into 8 Ohms. The other option spec'ed up to ±80V DC with 2x 15,000uF capacitors at 80V.

The connection is very simple. Connect + to +, - to -, GND to GND and Gate Drive to Gate Drive. Remember to remove the bubble 'Int GD' on the ZapPulse modules as shown if you are using the external supply for the Gate Drive! The modules are to be connected by short, thick wire connections, meaning very low losses. The Predator Power Supply is designed to be mounted with the PCB vertically, the diode bridges are screwed onto the metal chassis which doubles as a heatsink. You can use virtually any suitable transformer, ones with an extra 15V secondary can be used as well.

Transformer connection: Most modern transformers follow the shown colour coding standard. Yellow, Orange, Red and Black. Connect these wires in order from light to dark colour, or the other way around. Doesn't matter. If you are going to connect 2 transformers to the PSU remember that each transformer should be paralleled with itself (NOT the other transformer!!). In that case simply connect in the same order the wires in each 4 pole terminal of the Predator PSU. 15V AC for the Gate Drive should be connected to the 2 pole terminal.

There is a special terminal to connect an LED. Remember to use a series resistor. Depending on the LED use 2k2 to 10k.

Note: transformers, LED, SoftStart and DC Filter are not included.

LC Audio Predator Power Supply connections for ZAPpulse 800XE.

LC Audio Predator Power Supply with modules.

V4P Power Supply for Multiple ZAPpulse Modules

The V4P (virtual four pole) power supply board is mainly intended for driving multichannel ZAPpulse based amplifiers, like Home Cinema installations, from 4 channels up to 8 channels. It includes a DC noise filter and SoftStart circuitry.

ZAPpulse V4P 8-module power supply.

Features

• 68,000uF Low Impedance capacitors, connected in a V4P network.
• Ultra Fast Recovery (25 nS) rectifiers.
• Soft Start Circuit.
• DC Filter (prevents transformer hum).
• On Board Gate Driver Regulator.
• One Module Does it All.

Simplified principal of operation.

Power Supply Principal of Operation

Here you can see the principle of V4P networked capacitors. All capacitors are synchronously charged or discharged and none of the capacitors exchange charging currents. Every capacitor equivalent series resistance is about 10 milliohms but the combined series resistance to the neighbouring capacitor is about 200 milliohms. So no capacitor can exchange current with the others.

The 8 ultra fast rectifiers are placed on small separate heat sinks for better regulation. The SoftStart relay circuit enforces a slow cut in to the mains grid, avoiding stress to the rectifiers, switches and capacitor banks. A large value capacitor is used as a DC blocking capacitor, it prevents DC components from the mains supply from reaching the primary winding of the main transformer, where it would cause hum.

Construction Tips

Connection of the ZAPpulse V4P power supply is quite straightforward as the board has it all! Obviously care must be take as you are working with mains wiring, so ensure all wiring is double checked and suitable earthing and precautions are take. Note, we have removed one capacitor from the ZAPpulse module on this picture, to give you a better view of the wiring.

We recommend a transformer of 2 X 42V AC secondary, 500VA to drive 4 ZAPpulse modules and two 500VA's for 5 to 8 channels.

Connection of a ZAPpulse (early version shown) modules to power supply.

Connection of the V4P power supply and mains.