ZOLL E Series Monitor Defibrillator Rev D - Manual (Page 103)

E Series Service Manual
9650-1450-01 Rev. D 4-7
High Voltage Module
The High Voltage (HV) module includes the high voltage circuitry required for pacing and defibrillation, including the defib charge circuitry, patient relay,
safety relay, defib capacitor, defib choke and front end protection circuitry for the MFC ECG.
The following table describes the high voltage board components:
Component Function
Defibrillator Charging and Discharging
The defibrillator charges and discharges high voltage capacitor energy. A user can initiate a charge in three ways by 1) pressing the charge button on the
front panel; or (2) pressing the charge button on the paddles; or (3) configuring unit to charge automatically when it detects a shockable rhythm following
an ECG analysis. To initiate a discharge, a user depresses both shock buttons on the paddles or depresses a single shock button on the front panel.
The defibrillator circuit charges the high voltage capacitor to the energy level the user specifies.This circuit also provides feedback to the main system
board on the high voltage capacitor's voltage level and discharges the high voltage capacitor energy through paddles or the universal cable. The
defibrillator portion of the high voltage circuitry is active only when the front panel selector switch is set to DEFIB (or set to ON for AED units).
Charging
The charging process starts when the Main System Board detects a charge request. The defibrillator circuits begin charging the high voltage capacitor to
the target voltage or energy that the user selects on the front panel display. The Main System Board continuously monitors the capacitor voltage signal to
ensure that the high voltage capacitor charges at the proper rate. When the target voltage is reached, the Main System Board initiates a continuous beeper
tone to indicate that defibrillator is ready to discharge. The target energy level displays on the display screen.
The defibrillator holds the energy for 60 seconds for manual units and 15 seconds for AED units, refreshing the energy level as necessary. An intermittent
beep tone sounds during the last ten seconds (five seconds for AED unit) of the hold period. After the 60 second period, if the defibrillator has not been
Solid State Patient Relay Controls the delivery of therapeutic energy to patient.
Safety Relay Discharges Defib capacitor into the internal discharge
resistor when defibrillator is not in use.
Defibrillator Capacitor Stores energy for therapy.
Defibrillator Choke Conditions waveform delivered to the patient.(DSW)
Front End Protection Circuitry for
the MFC ECG Protects ECG front end against defibrillator pulses.