Underwater Electrical Control

1. Scenic Elements Motorisation

2. Objectives
To have a general understanding of how all the components work to
make the props move, and to have a better understanding of how
best to operate the props.

3. Subjects
❖Piff Paff Buttons
❖Piff Paff Reed Switches
❖E-Stops
❖Control Card
❖Potentiometer
❖Inverter
❖Motor & Drive Assembly
❖Batteries
❖Battery Chargers
❖Taking Props OFF Charge
❖Driving Advice
❖Putting Props ON Charge

4. Piff Paff - Button
Assembly
❖ Green Buttons - Drive (Spring Loaded)
❖ Red Button - E-Stop (O-Ring but No Springs)
❖ Button Base Houses Magnets
(Sealed with an O-ring)
❖ Magnet is Small and Cylindrical
MYTH’s
1. Rotating the button does not make the prop drive better.
2. The E-Stop is NOT a BRAKE !
3. E-Stop cannot come up on its own
IMPORTANT
1. E-Stop should be completely pushed/pulled. All the Way
IN or all the Way OUT.
2. If there are two Piff Paff controls, both E-Stop’s should be
engaged in order to avoid uncontrolled movement.
3. Drive Buttons should be pushed straight in.

5. Correct
Wrong
The Point is to make
sure that the button
is pushed evenly
down. To ensure the
magnet is as close
to the reed switch as
possible.
An example of
this was found
on the Bridge

6. Reed Switches
❖ Reed Switches are Wired as Normally Open
(Off) or Normally Closed (On).
❖ E-Stop is wired as Normally Closed (On).
When the E-Stop is Engaged (Pushed In),
the Circuit is Broken, and the Electrics are
Shut Down
❖ Drive Buttons are wired as Normally Closed
(Off) until the button is Engaged and the
circuit is made. The control card reads which
circuit is Closed and instructs the inverter to
provide power to the motor dependant on
which circuit it is, either Forward Fast/Slow or
Backwards Fast/Slow
Old Style
Very Fragile
Breaks Easily
No Longer in Use
New Style
More Robust

7. Reed Switches
❖ Although the new style (Encapsulated) reed
switches are more robust, it is still very
important to avoid banging on the Piff Paff. The
buttons including the E-Stop simply need to be
pushed by applying pressure. NOT by
hammering or banging.
❖ When new reed switches are installed, the
position is tested repeatedly before applying a
glue to hold them in position.
❖ If the button is pushed unevenly and off centre,
the magnet could be taken just out of range for
it to have an Effect on the Reed Switch.
❖ Not all magnets or buttons sit in an EXACT
same position as the others. This is why we test
each assembly repeatedly before signing off.
This is not an exact Science, so we TEST,
TEST and TEST !
There is no
electronics/brains in a Piff
Paff. It is simply a box with a
few sensitive ON / OFF
switches.

8. E-Stops
❖ The E-Stop works by opening the
circuit and cutting the power to the
electronics. NOTE : The E-Stop is not
a BRAKE, and so the prop may
continue to move a few centimetres
due to momentum.
❖ Reed Switches can and do FAIL !
❖ There is NO WAY to predict WHEN !
IMPORTANT
Engage ALL available E-Stops when
the prop is left unattended.
Example:
NE Russian Swing had a failed switch. Off-Stage
Fast.
The E-Stop was the only thing stopping the Prop from
moving. If only One E-Stop had been Engaged and
that Switch also Failed, a number of possible
Scenarios and Damage could have been caused.

9. Control Card
❖ Piff Paffs and Inverter are connected
❖ Receives signal from Piff Paff’s
❖ Sends instructions to the inverter
❖ Slow speed is adjusted through the use of
a potentiometer
❖ Fast speed is maximum, and cannot be
adjusted.
❖ Has a green indicator light to show activity

10. Control Card - Green Light
The Green Indicator Light shows the status of the card.
When E-Stop’s are Dis-Engaged, power is provided to the control card and inverter. The green indicator light will start to blink. This
blinking indicates the card and chip are starting up.
When the blinking has ceased the card is then ready to receive a signal from the Piff Paff’s. The time this takes may vary between
some of the props. At most, this is approximately 5 seconds.
Whilst this indicator light is blinking, pushing a drive button will have no effect. If you happen to push and release a drive button just
as the system goes into READY mode the prop may move unexpectedly, this is because for a split second the card will have
received a signal from the Piff Paff’s.
Movie

11. Potentiometer
The Slow Speed is a percentage of the full
speed. Adjusting the potentiometer will
adjust the percentage of the slow speed.
A small movement can make a big change.
There is no indicator to know what this
percentage is. Dry Testing is all we can do.
When working inside the prop electrical
boxes, be careful to not accidentally move
this dial.

12. Inverter
❖ Is the Power House
❖ Converts the 24V DC Battery Voltage to a 3 Phase
Output for the Motor.
❖ Receives instruction from control card and supplies
power to the motor depending on the instructions
received. Forward Fast/Slow or Reverse Fast/Slow.
❖ Also stores information regarding running hours and
history of 5 previous Error Codes
IMPORTANT
When driving a prop back and forth repeatedly without
allowing the inverter time to cool, it will overheat and will not
operate to prevent damage.
Alarm Code “AL61” Indicates “High Temperature”. Engage E-
Stops and allow 5-10 minutes for cooling. Drive the prop to a
safe place, and allow ample time for cooling.

13. Inverter - MDI Display
❖ Displays messages provided by the
inverter in the form off….
• Battery Status
• Run Time
• Maintenance Required / Alarm
• Alarm Indicator and Code
• Alarm Codes are Prefixed with “AL” and then a
number. The wrench symbol should also be
displayed along with a flashing red light.
To my Knowledge, these settings have never
been changed and so should be accurate

14. Motor & Gearbox
❖ Motor is 3 Phase, 3KW, 17V which max’s at
1500 RPM
❖ Power is Provided by the Inverter
❖ Gearbox has a Worm Drive which spins a
toothed wheel connected to a hollow axle
❖ Gearbox has a maximum Torque of 830 Nm
❖ It’s HEAVY !

15. Batteries
❖ 2x 12v 200Ah/10HR Batteries
❖ Are Wired in Series to give an output of
24v 200Ah/10HR
❖ They are Very HEAVY !
DANGER !
DO NOT drop the charging end base into the water.
DO NOT short the Battery Terminals
This will short the batteries and could cause a
fire/explosion hazard.

16. Battery Chargers
❖ High frequency chargers
❖ Has an external display
❖ Has an indicator displaying charger status
• Yellow Solid - Initial Charging
• Yellow Flashing - Charging Phase
• Green Flashing - Conservation (Trickle)
• Green Solid - End of Charge
• Red Flashing - Alarm
❖ Display during initial power up will first show the battery
voltage before starting to charge
❖ Display during charging shows the supplied voltage to
the batteries
❖ Display once charging is complete shows the Battery
Voltage
IMPORTANT
If the Displayed Voltage is Less than 24v and shows Solid
Green Full Charge, please inform Aquatics Day Crew.
Charging
Full Charge

17. Taking Props OFF Charge - Dry
1. Turn chargers Off
2. Wait for charger display to power down
3. Disconnect charging cable from charging hose
4. Check O-Ring condition in charging cap base
5. Check condition of charging cap and base
6. Securely fasten the charging cap to the base
ensuring that wires or the O-Ring are not
pinched. DO NOT hold the hose when doing
this. Hold the base and the cap only.
7. Remove charging hose from wall bracket
8. Place charging cap on the outside of the small
step surrounding the pool edge. DO NOT place
in the water until the electrical compartment of
the prop has been pressurised.
BAD GOOD

18. Taking Props OFF Charge -
Wet
Open Valve on
Pressure
Regulator
Check Electrical Box
Gauge for Pressure.
Is there Pressure ?
NoYes
Ascend and
Check Charging
Cap for Leaks
Check Gauge on
Buffer Tank.
Is there Pressure ?
Yes
No
Ensure Prop Air Line
is Connected
Properly. Did this
Solve the Problem ?
No
Look for
Noticeable Leaks
and Inform your
Superior or
Contact Day Crew
Leave Charging
Cap in the Water
Descend and pull down
the Charging Cap. Coil the
hose into the storage box.
Be careful not to snag the
Charging Cap on any
Obstructions. DO NOT
YANK on the Hose.
Check Charging Cap for
Leaks One More Time
before swimming away.
YesCheck Electrical Box
Gauge for Pressure.
Is there Pressure ?
No
Yes

19. Driving Advice
1. Always drive from the side of intended
travel direction* (You don’t drive a car
from the back seat)
2. Ensure the prop is ready to be driven. i.e.
Russian Swing’s raised, air lines
disconnected, path and tracks clear
3. Once the final E-Stop has been Dis-
Engaged, Wait 5 seconds for the Control
Card to power up. Keep hand over E-Stop
in case of uncontrolled movement
4. Always start with the slow speed button
before moving to the fast speed button
* Except when necessary i.e. Testing, Fault Finding, Small Adjustments etc..
5. Remember to allow for momentum when
planning on stopping
6. Make small adjustments using only the
slow button
7. When moves are complete, remember to
engage all E-Stops
8. Remember not to let the inverter
overheat. Have a break in between
driving sessions.
9. Whilst submerged, try to avoid leaving
the prop without a supply of gas for
extended periods.

20. Put Props ON Charge - Wet
1. Ensure prop air line is connected
2. Check for any noticeable leaks
3. Shut OFF the regulator ball valve
4. Take the charging hose end to the
surface and place out of the water
5. Ensure the hose is not wrapped around
any obstacles
OPEN
CLOSED

21. 1. Secure hose into wall mounted clamp
2. Use the correct tools and remember “Righty Tighty, Lefty
Loosey"
3. Without holding onto the charging hose, unscrew the charging
cap from the charging cap base until you hear a steady flow of
gas venting
4. Be Patient ! It will take a few minutes for the pressure to
completely drain
5. Do Not unscrew the cap fully until all the pressure has been
released. Doing this does cause damage to the threads
6. If the pressure takes longer than 10 minutes to vent, check that
the valve on the prop regulator has been Closed
7. If the valve is Closed and still takes longer than 10 minutes,
inform your superior and/or inform day crew
8. When cap is removed, connect the charging lead
9. Turn On the power to the battery charger and watch the display
10.After ensuring the charger is charging, you may walk away. If it
does not go into charging mode, inform your superior and/or day
crew
Put Props ON Charge - DRY

22. QUESTIONS

23. Help Us
When issues arise, please come to us with more information
than just “it does not work”, “it does not drive”, “it drives slow”
or “it’s driving on its own”.
The Clues are in the Details
Do the Electrics power up?
What is the Voltage?
Does the Green Light on the control card turn
on when the drive buttons are pushed?
Can you hear the motor running when a drive button is pushed?
Are the wheels & tracks clear?
Is there an Alarm Code displayed?
Do any of the drive buttons make the prop move?
Do the drive wheels slip?
Does the prop drive the same whether it is on stage or off stage?

24. Decisions
Is it a Piff Paff issue?
Do we need to open the box?
If so, how long do we have?
To open – 15min
Fault Find ????
To Repair / Replace ????
To close – 20 min
To Pressurise – 5 min
Leak Test Underwater – 5 min
The more accurate the information is, the Quicker we might be able to Solve
We need at least 2 hours if the decision is made to open the box
One Piff Paff can be replaced in 20 minutes