Chapter 3: Installation and Testing
33
3.10.2
Single throttle wiper
Connect the throttle potentiometer ends to
T+
(Throttle Positive, pin 2) and
T-
(Throttle
Negative, pin 8). Connect the throttle wiper to
TW
(Throttle Wiper, pin 1).
To use this option, set the
Throttle Input
parameter (4.4.2.2) to 'Single'.
Warning:
If the throttle potentiometer is powered externally (not by T+ and T-), take extreme
care to avoid ground shift. The R
HINO
2 can interpret a ground shift voltage as a
drive signal and the scooter might start driving. If the throttle must be powered
externally, either use additional hardware as described below or use the Neutral
Detect feature (see 3.10.3) to detect a ground shift and prevent a potential
runaway.
3.10.2.1
Additional hardware to comply with ISO7176-14 2008
To make a single throttle wiper configuration compliant with the standard, extra hardware is
required to check if the throttle signal is valid.
One way to achieve this is to use a Neutral Detect (ND) switch that indicates if the throttle is
in the physical neutral position.
Normally, the hardware transfers the Throttle Wiper voltage to the TW output directly.
However, if the ND switch indicates "Neutral", but the wiper signal is not at the neutral value,
the hardware must set the TW output to a "fault" value (higher than
Maximum Throttle
Voltage
or lower than
Minimum Throttle Voltage
, see 4.4.2.8). A "fault" value causes the
controller to generate a fault and prevent driving. This makes sure that the scooter will never
drive if the throttle wiring is faulty. See also Throttle Testing (4.4.2.7).
The
R
HINO
2
offers a Neutral Detect input, to which a Neutral Detect switch can be
connected directly without the use of additional hardware.
See the next section for details.
T-
0 V
5 V
T+
TW
5 kΩ
Additional
Hardware
Neutral Detect
5 kΩ
Throttle
Throttle Wiper
T+ (Pin 2)
T- (Pin 8)
TW (Pin 1)
B+
B-