General questions
I just unpacked my scooter and it does not work.
Every Seacraft scooter is sent with disconnected main battery connector – for safety reasons.
You have to open the unit, and connect the battery.
You have to open the unit, and connect the battery.
What is the estimated battery lifetime? Is there anything that can be done to extend it?
Li-Ion batteries lifetime determination is a very complex topic, with numerous factors influencing the result.
In general, a gradual decrease in total Li-Ion battery capacity can be observed over its usage cycle.
Seacraft batteries use a custom-made BMS (battery management system) which takes care to correctly balance the cells, and extend its life to the maximum. Under regular usage (moderate gears – 4-8, discharge from 100% to 20%, good storage conditions) it should survive ~500 charging cycles/ 5-8 years until the total battery capacity falls to 80%.
However, the factors that will affect battery life time in the biggest way, are:
-Storage temperature. If batteries are stored/ used/ charged in hot conditions, this will significantly affect their lifetime. Try to keep the battery in cold conditions (5-15*C) when not used, in order to prolong its life. Limit exposure to heat.
-Storage voltage. Storing batteries charged to 30-50% is the best for their durability.
Storing a fully discharged battery (0%) will lead to its irreversible damage. If the DPV battery is fully discharged, make sure to charge it immediately to a minimum of 20%.
Try to not charge your scooter after a dive, but keep it at the remaining charge level (30-50% recommended), and recharge just before the next dive.
-Usage. If DPV is used on the maximum speed constantly (top gear), the battery is loaded with a higher current, and it will result in a shorter lifetime.
In general, a gradual decrease in total Li-Ion battery capacity can be observed over its usage cycle.
Seacraft batteries use a custom-made BMS (battery management system) which takes care to correctly balance the cells, and extend its life to the maximum. Under regular usage (moderate gears – 4-8, discharge from 100% to 20%, good storage conditions) it should survive ~500 charging cycles/ 5-8 years until the total battery capacity falls to 80%.
However, the factors that will affect battery life time in the biggest way, are:
-Storage temperature. If batteries are stored/ used/ charged in hot conditions, this will significantly affect their lifetime. Try to keep the battery in cold conditions (5-15*C) when not used, in order to prolong its life. Limit exposure to heat.
-Storage voltage. Storing batteries charged to 30-50% is the best for their durability.
Storing a fully discharged battery (0%) will lead to its irreversible damage. If the DPV battery is fully discharged, make sure to charge it immediately to a minimum of 20%.
Try to not charge your scooter after a dive, but keep it at the remaining charge level (30-50% recommended), and recharge just before the next dive.
-Usage. If DPV is used on the maximum speed constantly (top gear), the battery is loaded with a higher current, and it will result in a shorter lifetime.
I have problem with opening my scooter’s hull – it is very hard.
After trimming, the scooter does not need to be opened at all, as it is externally charged. However, there are some tips which will make opening the body easier:
– Make sure that cap nut is completely removed.
– Stand on the noozle (it is strong!), and gently “wiggle” the tube, simultaneously pulling it upwards.
– Before reassembly, apply dedicated Seacraft seals grease to the o-rings. It is also good to grease internal part of the tube, where it covers the o-rings what will make opening of the body easier.
– A tansport handle attached to the body helps significantly to pull the tube up.
With time, grease on seals is being squeeed away by o-rings compression, what will make it more difficult to open after for example a year of inactivity. Greasing the inner part of the tube ensures that after one harder move, the whole process will be easy even after long closure times.
– Make sure that cap nut is completely removed.
– Stand on the noozle (it is strong!), and gently “wiggle” the tube, simultaneously pulling it upwards.
– Before reassembly, apply dedicated Seacraft seals grease to the o-rings. It is also good to grease internal part of the tube, where it covers the o-rings what will make opening of the body easier.
– A tansport handle attached to the body helps significantly to pull the tube up.
With time, grease on seals is being squeeed away by o-rings compression, what will make it more difficult to open after for example a year of inactivity. Greasing the inner part of the tube ensures that after one harder move, the whole process will be easy even after long closure times.
My scooter does not charge to 100% – how does the % calculation work?
There will be never a 100% charge displayed – maximum percentage is 99% (due to the displayed numbers limit) If your scooter shows 96-99% after charging completion, everything is good and it is normal behaviour.
Some information about how Seacraft battery % display algorithm work:
– Seacraft uses an enhanced voltage-based algorithm, which accounts battery voltage, it’s internal resistance, and load.
-It provides relativelly precise indication and information about battery charge % – however, some factors may influence it’s display.
– In high temperatures internal cell’s resistance decreases, in cold ones, increases. This leads to behaviour similiar as when loading diving tanks- hot battery will read more %, and after cooling down it can read even few % less.
– Charging stops automatically when reaching certain battery %. This means that in high temperatures charging will stop earlier.
– Another factor is scooter’s work. When battery is loaded, it delivers power- what leads to power drain, and voltage drop. If starting scooter immediatelly on high gear, it may cause a sudden battery % drop by few percents.
Another very important factor is correct setting of battery installed in the DPV– each battery has different charcteristics, and assagning wrong battery type may influence the readings.
Some information about how Seacraft battery % display algorithm work:
– Seacraft uses an enhanced voltage-based algorithm, which accounts battery voltage, it’s internal resistance, and load.
-It provides relativelly precise indication and information about battery charge % – however, some factors may influence it’s display.
– In high temperatures internal cell’s resistance decreases, in cold ones, increases. This leads to behaviour similiar as when loading diving tanks- hot battery will read more %, and after cooling down it can read even few % less.
– Charging stops automatically when reaching certain battery %. This means that in high temperatures charging will stop earlier.
– Another factor is scooter’s work. When battery is loaded, it delivers power- what leads to power drain, and voltage drop. If starting scooter immediatelly on high gear, it may cause a sudden battery % drop by few percents.
Another very important factor is correct setting of battery installed in the DPV– each battery has different charcteristics, and assagning wrong battery type may influence the readings.
FUTURE
I have problem to trim my unit in fresh water – the nose is too light.
Seacraft engine is located- due to unique construction- on the end of the scooter. This locates a big mass on the end of the scooter, which- to achieve neutral trim- need to be countered. In case you have one of the 2017 series scooters, it may require moving the battery and weights to the absolute tip of axial pipe. In case that you are mounting for example also a ENC navigation console on the scooter, you may want to ask us for new weight mounting system- which allows to move it even closer to the front:
GHOST
What is buoyancy backup in Ghost1500 and Ghost2000?
Ghost 1500 is often chosen by videographers and divers assembling a lot of extra gear onto DPV, because it has ~1200g of buyoancy backup in fresh water.
Ghost 2000 has maxed-out battery capacity, still providing ~200g of lift in fresh water. In salt water (38 promiles salinity) both units will have ~600g buoyancy backup more.
Buoyancy backup determines how much weight (negative buoyancy) can be assembled on the scooter, and still trim it neutral.
Ghost 2000 has maxed-out battery capacity, still providing ~200g of lift in fresh water. In salt water (38 promiles salinity) both units will have ~600g buoyancy backup more.
Buoyancy backup determines how much weight (negative buoyancy) can be assembled on the scooter, and still trim it neutral.
I cannot discharge the battery – it is my 6th dive, and battery is still over 50%.
You probably have the best scooter on the market. It is normal – do not worry, and… tighten the mask strap.
