Safety¶
LiPo battery handling¶
The boat uses a large capacity lithium polymer (LiPo) battery. Aside from the large capacity, this is a typical RC hobbyist battery. With proper handling and avoiding abuse, the LiPo batteries are not safety hazards. However, if they are mishandled or abused, they can create fire hazards.
A LiPo has five important voltage levels:
- Peak = 4.2 V per cell (16.8 V for a 4S battery)
- Storage = 3.8 V per cell (15.2 V for a 4S batter)
- Nominal = 3.7 V per cell (14.8 V for a 4S battery)
- Drained = 3.5 V per cell (14 V for a 4S battery)
- Damaged = 3.0 V per cell (12 V for a 4S battery)
When operating the boat, not drain the boat’s battery below the “Drained” voltage if at all possible. Draining it below this value should be done only if you need to recover the boat. It is hard to predict how draining the battery below 3.5 V per cell can affect the long-term health of the battery, so it is best to avoid it entirely.
NEVER drain the battery to the “Damaged” voltage or lower! Doing so can lead to the battery entering a state where physical impact can puncture the cells, creating a serious fire hazard!
If a LiPo battery is drained too far, it will become “puffy”. Normally the battery will be a rigid brick of materials, but a puffy battery will have expanded like a ballon.
NEVER recharge or use a puffy LiPo battery!
General electrical circuit handling¶
The boat’s battery is capable of a very large output current, especially in the case of an electrical short.
Avoid directly touching any circuit boards while the battery is connected to the boat. Unless otherwise noted, only connectors, buttons, and switches are meant to be handled.
The XT90 connection between the battery and the cable harness has exhibited a vestigial voltage that lasts for some time after disconnecting the battery. When handling this connector (e.g. plugging and unplugging a battery) make sure you only touch the yellow plastic.
Water in the internal compartments¶
As noted above, electrical shorts are a risk for any electrical system. Water entering the compartments, especially the front compartment, can cause electrical shorts between any of the electronics installed there.
It is quite common to have a small amount of water in the rear compartment, but the front compartment should remain dry. If you see water in the front compartment, immediately shut off the boat, remove the battery, and dry the components!
Try to identify the leak ingress point - there is something very wrong if you see water in the front compartment!
One common way water can enter the front compartment is if the white housing lid is dripping wet and you hold it over the open compartment. If you are about to open the front compartment, make sure the lid is dry.
Fast-spinning propellers¶
Simple rule - never directly touch the motors, propellers, or airfan while the boat is on.
When you are inspecting the propellers, set the boat down so that the propellers are free to spin in the air.