Emerson MPR15 Series User Manual

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NT5C06B / C   Installation and User Manual 

The main AC line voltage is rectified and filtered to an unregulated high DC 

voltage. The input circuit provides EMI filtering, inrush current limiting, low 

and high AC inhibition, lightning and surge voltage protection, and input 

fault protection through an AC breaker. 

The high frequency isolating power section consists of a full bridge 

converter using power MOSFETs and a high frequency power 

transformer. 

The high frequency AC voltage generated at the secondary of the power 

transformer is rectified and filtered. The output section provides EMI 

filtering, a shunt for output DC current sense, and output protection in 

the form of a DC breaker. A current mode pulse width regulator varies 

the pulse width of the signal driving the power MOSFETs. This allows 

regulation to the output DC voltage. 

The monitoring circuitry includes soft start, rectifier fail alarm (RFA), 

rectifier RFA/ON LED, local and remote equalize, temporary release, 

thermal shutdown, AC valid, local and remote high voltage shut down 

(HVSD), local and remote HVSD reset, logic valid, fan failure detection, 

and a fan failure LED. 

A three-digit output current meter reads the output shunt and displays 

the value using an integrated logic circuit. 

An auxiliary power supply provides the various voltages required by the 

internal circuitry and cooling fan.