Technogym FORMA LINE BIKE FORMA DDC5 Series Technical Assistance Manual page 26

The higher the value of the Current sent by the Brake Board to the winding, the greater the
Resistance produced. In addition, when the excitation of the brake is the same, the higher the speed
of the disk rotation, the higher the resistance produced.
Heat energy is dissipated on the brake disk due to the eddy currents.
The control over the CURRENT is CLOSED LOOP. The Brake Board calculates
which level of current to send to the brake winding, commands for it to be supplied
with a special driving circuit, and lastly checks that it is actually reaching the brake
through a reading circuit and the A/D conversion of the signal of the current as read.
The control over the RESISTANCE that is actually present on the pedals (effective
user torque) is via OPEN LOOP. The system (Brake Board) + (brake) does not
envisage any regulation in order to adjust the value of the resistance produced, but
solely the use of the braking value table as memorized on the Brake Board. The
precision of the braking system has a tolerance of ±10%.
Certain pieces of equipment (e.g. floating ones, but not only those) as opposed to the common training
sessions with constant torque and constant power, provide for a training mode with constant speed level.
With this kind of training, the Brake Board always operates a CLOSED LOOP control over the CURRENT,
but does not operate any control over the RESISTANCE, since it only needs to maintain a constant RPM
value. In practice, in addition to the control over the CURRENT, the Brake Board exercises in this case a
CLOSED LOOP control over the RPM, since it knows the target value to be achieved. It activates the
current to achieve it and constantly reads the RPM value on the speed sensor so as to converge the control.
During movement, the speed sensor detects the heads of the screws that fix the disk of the brake and
produces a signal representing the speed, which is sent to the Brake Board. The Brake Board will
regulate the excitation current to the winding so that the speed measured by the speed sensor
corresponds to the set speed.
If the Brake Board does not receive the speed signal which confirms that an exercise
is in progress, the equipment does not produce any resistance (current equal to zero).
This occurs mainly for two reasons: the equipment is stationary or there is a problem
with the RPM pick up.
During movement, the Brake Board is capable of detecting possible faults. Any possible errors are
detailed in paragraph: 6.4. "The Brake Board has detected an error".
In all circumstances, the Brake Board interrupts the supply of current to the brake, the green LED
switches from "on" to flashing mode and sends an appropriate error message to the Display Board
which visualizes the following message on the display: "THE EQUIPMENT IS BLOCKED.
CONTACT THE TECHNOGYM TECHNICAL SERVICE (X)", where "X" represents the Error
Code for the error that has occurred.
Other error codes that may be displayed on the high kit but are not included in the
table and are different from (COM), do not relate to the POWERED kind of Brake
Board.
Page 3.8
Forma Line BIKE FORMA (DDC5): Technical Assistance manual - rev. 1.1