DOWNLOAD Panasonic KX-TDA0103X / KX-TDA0103XJ / KX-TDA0104X / KX-TDA0104XJ / ETX1KM753MB / ETX1KM752MB Service Manual ↓ Size: 4.91 MB | Pages: 105 in PDF or view online for FREE

13

This section generates the Alarm signal such as AC ALM, DC ALM and FAN ALM

1. AC ALM Signal Output

The detection of AC is done on the Primary and the information is transmitted to the secondary side via PC001. 
AC ALM is generated by the IC133 by monitoring the condition of the transistor side of PC001.
IC133 : Voltage monitoring IC with delay.
Q134 : Open Collector Output buffer transistor for AC ALM

2. DC ALM Signal Output

The detection of each of the output voltage of 15VP, 30V and 41V. 
DC ALM is sent out when any of the output voltages drop below the pre-set value or when AC ALM is activated.
However, when a working Battery is connected to CN604 DC ALM is not sent out during the period AC ALM is activated while 
the DC output voltages are within the pre-set value.
SW601: Battery Backup On/Off control
Q165, D135, Q133: Negate the sending out of DC ALM during AC fail and Battery backup is activated.
IC131, IC132 : Comparator IC for detecting the status of each output.
Q130: Open Collector output buffer transistor for DC ALM

3. FAN ALM

Send an alarm signal to the PBX system when the Fan stop operation.
Fan Stop signal is generated by the fan
Q202 : open Collector Output buffer transistor for FAN ALM

14

This section provide the shutdown function when any of the following condition occurred; 

i) Over voltage is detected on any of the outputs
ii) 15V output is shorted for a slightly extended period of time
iii) Over heating is detected on the secondary heatsink
iv) Over heating is detected on the Primary heatsink (Signal is supplied directly to primary PWM IC001)

TS001 : Primary Heatsink over heat detecting thermostat
TS101 : Secondary Heatsink over heat detecting thermostat
IC164 : 15V over current detecting IC
R208 : 15V current sensing resistor
ZD201 : 15V over voltage detecting zener diode
ZD301 : 15VP over voltage detecting zener diode
ZD501, ZD502 : 30V over voltage detecting zener diode
ZD103, ZD107 : 41V over voltage detecting zener diode
PC002 : transmit the abnormal detection to the Primary PWM to latch off.

15

This section provides the charging function (AC operation) and Back up function (AC fail) to the power supply when an appropri-
ate battery is connected to CN604 and SW601 is switched to ON.

1. Charge Mode

When the AC is available and an appropriate battery (approximately more than 20V) is connected to CN604, the power supply 
will charge the battery at a constant current.
Q667 : Charge mode pass MOSFET
R604 : Charge current sensing resistor
Q663 : current control transistors
K601 : Relay off if the battery is lower than 20V to prevent overheating the pass element

2. Back up Mode

When the AC failed and an appropriate battery (approximately above 27.5V) is connected to CN604 and SW601 is switch to 
ON, the power supply will maintain regulated outputs (except 41V output which will drop in tandem with the battery voltage.)
K601 : Relay off if the battery is below the range (27.5 to 30.5V) to prevent over draining the battery.
D667 : Back up Mode Pass MOSFET
IC661, IC662 : Battery voltage detecting IC
F601 : Protection Fuse open during abnormal operation of battery.

16

This section consists of the AC input connection and EMI noise filter

1. AC Inlet and Connector CN005

3 pin AC inlet and wire to board connector
Allow AC connection via the external metal chassis to the Power supply circuitry

2. SW001

Double pole rocker ON/OFF switch
Allow the switching On and Off the AC supply to the power supply unit

3. F001

5 x20 mm fuse with fuse clip
Provide the protection against abnormal current into the power supply by cutting the L line in hazardous situation.

4. Filter and Surge absorber circuit

Z001 : ZNR
Provide protection against external surge such as lightning surge
C027, C031 : Across-the-line EMI filter capacitors (X-cap)
L011, L012 : Common mode line filter 
C028, C030, C032, C033 : Line-to-Earth capacitor (Y-cap)
Limits the EMI noise generated by the power supply