Terumo BCT Trima Accel, Service Manual

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Power System
Power Switch and Circuit Breaker
The power switch, a toggle switch near the top of the right side panel, directs line current to the primary
side of the power supply. The main line circuit breaker has a black toggle handle and is located in the
bottom rear of the machine near the power entry. The circuit breaker is a magnetic system for greater
accuracy. If line voltage is 220 V AC to 250 V AC, the circuit breaker trips at 4 amperes. If line voltage is
100 V AC to 125 V AC, the circuit breaker trips at 10 amperes. The power entry is IEC-320, compatible
with a cord-retaining hood.
Power Supply
The DC power supply provides six secondary power supplies to the system. All secondary supplies have
over-voltage and over-current protection. If an over-voltage occurs, the power supply generates a “Power
Fail Warning” logic signal, latching the power supply outputs off. Turn the main power off and back on
again to restart the power after this type of event. If an over-current condition occurs, the power supply
generates a DC power bit “Not OK” signal, monitored by the control CCA. Serial Number 1T4296 and
below were manufactured with the old-style power supply that requires an external tool to test the over-
voltage and over-current protection. The new-style power supply is capable of performing its own over-
voltage protection testing internally. There are test points for over-voltage for each secondary power
supply. There are three LED indicator lights on the new power supply: the green LEDs indicate that the
DCOK and ACOK signals are within specification, and the yellow LED indicates OVP detection.
Table 2-14: Power supply voltages
+64 V DC
The +64 V DC secondary power supply powers the centrifuge motor. A shunt regulator circuit
in the DC power supply dissipates electromotive force (EMF) from the centrifuge motor when it
brakes to a stop. LEDs on the control CCA indicate the status of +64 V switched and unswitched
supplies. If the LEDs are lit, the supplies are within normal range.
+24 V DC
The +24 V DC secondary power supply powers the pump motors, the valve motors, the linear
actuator motor, the alarm lights, the fans, and the centrifuge door-lock solenoid. LEDs on the
motor driver CCA indicate the status of the +24 V switched and unswitched supplies. If the
LEDs are lit, the supplies are within normal range.
+12 V DC
The +12 V DC secondary power supply powers the audio speaker, the display backlight, and the
operational amplifiers on the RBC detector CCA. It is used as a voltage reference on several
cards and as the excitation voltage for the two air detector circuits. It also drives the LEDs on
the RBC detector CCA. An LED on the control CCA indicates the status of the 12-volt supply. If
the LED is lit, the supply is within normal range.
-12 V DC
The –12 V DC secondary power supply powers the operational amplifies on the motor driver
CCA and the RBC detector CCA. An LED on the control CCA indicates the status of the –12 V DC
supply. If the LED is lit, the supply is within normal range.
System Description
2-66 Trima Accel
®
Automated Blood Collection System • Service Manual