GE T2100, Service Manual

Page: 54 / 152

5-4 GE T2100 Treadmill Revision A
2021403-031
Theory of Operation: Power Board (PCB) Theory
Power Board (PCB) Theory
General Description
The power board and processor board function together as part of the e-
box to control the GE T2100 Treadmill. The power board contains the
following:
!
Mains components
!
Isolation transformer
!
Elevation and drive interface circuitry
!
Interface to processor board
Precautions
Handling of this power board or harness should be done by qualified
service personnel observing customary EST protections procedures.
Initial Board Conditions
The power board initial conditions are all at 0V.
Power Input Requirements
The GE T2100 Treadmill is used on single phase AC. The specific power
ratings are 200-240VAC, 50-60 Hz, 16A.
Power Distribution/Isolation
The power board receives 200 to 240VAC power (nominal 220V). The
isolation transformer supplies 12V to two switching regulators. The
switching regulators 5V to both the isolated side and the non-
isolated side of the processor board. Bypass caps are distributed across
the board to minimize EMI and power supply noise.
Power Inlet, Drive Power Outlet & Mains
The power comes in on the terminal block, gets fused and filtered, and is
distributed to the isolation transformer, out to the drive system and to a
+24V power supply. Externally accessible 0.5ASB fuses are provided for
the control portion of the circuitry. A 2.5 Amp internal fuse is dedicated
to protecting the +24V power supply. The 25 Amp internal fuses are for
the drive section and are intended to protect the wiring from major faults
within the drive system. Spacings for creepage and isolation are critical
in this whole section.