SCIFIT ISO7000R, Service Manual, Page: 7 / 82

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Electromagnetic Brake
o
An eddie current transformer that uses rising and collapsing
electromagnetic fields to slow down the generator magnet traveling
through it’s field.
o
Controlled by the lower PCB.
4. 12 Volt DC Battery
A. 12 volt sealed lead acid 1.3 Amp Hour Battery.
B. Provides 12 Volts DC to lower PCB during:
o
Pause mode
o
Between intervals
o
Provides power for 15 seconds after generator stops.
5. Wall Pack Receptacle
A. 12 volt DC input receptacle that accepts voltage from a DC wall pack.
B. Provides 12 volts DC to lower PCB when a wall pack is connected to it.
C. Aids in battery charging.
6. Hand Grip (Contact) Heart Rate (HG HR) PCB
A. Outputs a square wave to the upper PCB.
B. Equipped with right and left grip inputs.
C. Power and ground is provided by the upper PCB.
7. Wireless Heart rate PCB
A. Outputs a square wave to the upper PCB.
B. Has a 30” range and position is critical.
C. Power and ground is provided by the upper PCB.
System Functions
Starting the Machine
A. Pedaling the machine rotates the generator, which generates a
current to power the electronics. A minimum of 13 RPM or 10 FPM
must be maintained to keep machine powered up.
B. The generator provides AC voltage to the lower PCB. The lower
PCB then provides DC voltage to the upper PCB.
C. The User controls the resistance by selecting a level on the display.
The display sends a PWM signal which varies, depending on the
level selected. The signal travels through the ribbon cable to the
lower PCB. The lower PCB sends a square wave signal to the
transformer on the brake which is proportionate to the amount of
resistance commanded.
D. The brake LED on the lower PCB, labeled D38 on older units and
D19 on newer units, will illuminate any time braking is applied. The
intensity of the LED is proportional to the level of resistance.