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1.4 SAFETY & PROTECTION FEATURES
- Reverse Battery Polarity.
Electrical Circuit diagrams must be followed in order to avoid damage to the power
unit. A Main contactor, controlled by the logic unit, is necessary to protect the system
against reverse battery polarity.
- Connection errors
All inputs are protected against connections errors. Contactor drivers are suitable for
loads up to 2 Amps, and are protected against overload.
- Thermal protection
If the controller temperature exceeds 77°C, the maximum current will be reduced
proportionaly to the thermal increase. The temperature can never exceed 90°C.
- Low Battery charge
When the battery charge is low, the maximum current is reduced.
- External Agents
The chopper is protected against dust and spray of liquid to a degree of protection
meeting IP64.
- Protection against accidental Start Up
A precise sequence of operations is necessary before the machine starts. If these
operations are not carried out correctly the machine stops. Driving requests must be
made after closing the Key Switch.
- Protection against uncontrolled movements.
The Main Contactor will not close if:
- The Power Unit is not operating correctly
- The Logic Unit is not operating correctly
- The Serial Tiller is not operating correctly
1.5 THERMAL CONSIDERATIONS
- The heat generated by the power block must be dissipated. For this to be possible,
the compartment must be ventilated and the heat sink materials ample.
- The heat sink material and system should be sized on the performance requirement
of the machine. Abnormal ambient air temperatures should be considered. In
situations where either ventilation is poor, or heat exchange is difficult, forced air
ventilation should be used.
- The thermal energy dissipated by the power block module varies and is dependent
on the current drawn and the duty cycle.
