Refurbished Patient Monitor Parts Ventilator Power Supply Module For Hospital

Covidien Puritan Bennett 840 Ventilator Power Supply Module For Hospital

The power supply is a single FRU (Field Repairable Unit) with outputs +5, +12, +15 and -15 V to power the ventilator system. It also provides DC power for BPS charging. Power input is AC power from facility power or BPS DC power (battery power). The power supply accepts 80 to 269 V ac rms input at 47 to 63 Hz. Specifically, the output of the power supply is as follows:

• VH +5 V (remote sensing)

• VH +12 V

• VH +15 V

• VH -15 V

• GUI +5 V (remote sensing)

• GUI +12 V (remote sensing)

• BPS +36V

• Relay +12 V (from primary)

The power failure circuit in the power supply detects a drop of bulk +31.5 V (input of the power main converter) and notifies the BD CPU PCB. The BD CPU PCB in turn generates non-maskable interrupt (NMI) signals.

The AC monitor circuit provides an analog voltage proportional to the AC input voltage. This voltage is fed to the AI PCB and monitored by software. The power supply is protected against rated line transients, overheating, overload and short circuit conditions.

The power supply has no test points and cannot be adjusted in the field. Displays the supply voltage during the EST's analog data display test.

Power to the DC/DC converter in the power supply comes from the system's AC power supply or the BPS DC power supply. If AC power is available and sufficient, the power supply converts it to +31.5V nominal and radiates it from the mains supply. However, if the output of the bulk power supply is insufficient (<+31.5 V, equivalent to <80 Vac), the DC/DC converter uses the BPS power supply (+19 to +30 V).

Power loss and BPS switching. An AC monitor produces a voltage proportional to the AC input voltage. Adds AC monitoring voltage to AI PCB for software reading. When the AC monitor voltage drops such that the fan can no longer support the compressor, a signal from the compressor software and power supply turns off and the BPS board opens the corresponding BPS battery switch. The software continuously tests the BPS status bar and when it determines that the BPS is supplying power to the fan, the fan immediately issues a low emergency alarm. The GUI displays the warning messages "AC POWER LOSS" and "Battery Running". (A new fully charged BPS can run the fan (BDU) (excluding compressor and humidifier) ​​for at least 30 minutes.) When the fan estimates 2 minutes of battery remaining, the alarm level will be updated to medium emergency and the fan will display the message "Running time <2 changes to "minute".

Totally lost power. When the BPS is discharged to the point where the BDU is no longer operational (<+19.30V), the power cut-off circuit in the power supply senses the loss of power to ground (input to the mains converter). ) and informs the BD core processor board. The BD CPU PCB, in turn, generates an unmaskable interrupt (NMI). The software triggers emergency alarms at a steady rate. The capacitive drive BD alarm sounds. Even if the BDU does not function properly when powered off, there is still enough power for the GUI to continue displaying the text and displaying the current alarm status via the LED array.

Removing power supply assembly

1. First open the spring cover of the shielded power connector, then loosen the two 1/8" captive screws of the connector to disconnect the BPS cable. (3 mm) flat-blade screwdriver.

2. Remove the two screws that secure the power supply assembly to the BDU chassis. Gently pull out the power supply assembly to remove it from the connector. Place the assembly on a sturdy surface.

Install the power supply

1 Oriented power supply assembly with sloped heatsink section on top

2. Gently slide the power supply assembly into the BDU chassis until fully inserted.

3. Install two screws and tighten until snug.

4. Open the spring cover of the shielded power connector, connect the cable and, using 1/8 inch, connect the BPS cable to the power supply. (3 mm) flat-blade screwdriver for tightening the connector's two captive screws until snug. Do not overtighten.