LZ design FES LCD Display User manual

FES Quick Guide
Version 1.3
LZ design d.o.o., •Brod 3D, 1370 Logatec, Slovenia •[phone]
[email protected] •www.front-electric-sustainer.com

FES Quick Guide, v1.3 May 2020
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Table of Contents
1. Important notices..................................................................................................... 3
1.1 Limited Warranty ................................................................................................. 3
2. General.................................................................................................................... 4
2.1 Important voltages and temperatures ................................................................... 6
2.2 Preflight Test Run ................................................................................................ 6
3. Available FES manuals .............................................................................................. 7
4. Technical data.......................................................................................................... 7
5. FES drawings ........................................................................................................... 7
6. Maintenance ............................................................................................................ 7
7. Repair and service.................................................................................................... 7
8. Revision history........................................................................................................ 7

FES Quick Guide, v1.3 May 2020
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1. Important notices
This guide contains essential information about the safety of the Front Electric
Sustainer (FES) system, on the ground and during the flight. Even though FES is easy to
operate, a basic understanding of the system and its operation is still required, as it is
quite different from other propulsion systems.
FES Quick guide was prepared for pilots to read before their first flight with an FES
equipped sailplane to use FES safely and adequately.
This guide should only be used as a help to refresh the knowledge before flying and
not as a substitute for reading the complete system manuals. Users should check for the
latest versions and review the complete system manuals at least annually.
Information in this document is subject to change without notice. LZ design reserves
the right to change or improve their products and to make changes in the content of this
material without obligation to notify any person or organization of such changes or
improvements.
Caution: Yellow triangle is shown for parts of the manual which should be
read carefully and are important for proper operation.
Warning: Notes with a red triangle describe procedures that are critical and
may result in reduced safety or may lead to a critical situation.
Note: A bulb icon is shown when a useful hint is provided to the reader.
1.1 Limited Warranty
This LZ design FCU product is warranted to be free from defects in materials or
workmanship for two years from the date of purchase. Within this period, LZ design will,
at its sole option, repair or replace any components that fail in normal use. Such repairs or
replacement will be made at no charge to the customer for parts and labor. The customer
shall be responsible for any transportation cost. This warranty does not cover failures due
to abuse, misuse, accident, or unauthorized alterations or repairs.
LZ design retains the exclusive right to repair or replace the unit or software, or to
offer a full refund of the purchase price, at its sole discretion.
To obtain warranty service, contact your local LZ design dealer or contact LZ design
directly.
© LZ design. All rights reserved

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2. General
Before the flight, correctly fasten both batteries. Power cables connected to plus
and minus terminals should be fully engaged and signal cable with two multipole
connectors plugged into the battery packs.
Warning: Before trying to plug in the male connectors, make sure the
orientation is correct. Do not use excessive force! If the connector does not
fit the socket, the orientation of the connector is likely wrong. Insert it
aligned straight with the socket; otherwise, pins could be damaged!
Pilots new to FES should respect the following procedures:
1. When you are not using the glider on the ground, make sure that
"Connecting cable" is NOT inserted in the FES battery packs! For example,
when you store the glider in a trailer, park it in the hangar or when you park the
glider for extended periods before or after landing. By doing so, the FES system is
not operational on the ground.
2. Install the "Connecting cable" of the FES battery packs for a preflight check. The
DC/DC converter starts providing 12V to the FES system and other instruments, as
well as charging any 12V batteries on board.
Switch ON the Battery Management System (BMS) by using the electronic BMS
switches on top of each battery pack, after you have installed the "Connecting
cable". This ensures that the FCU instrument receives temperature and cell voltage
data. At this point, the system is "ready for flight", but high voltage supply to the
motor is inactive.
3. Turn ON the "Master switch". On some Schempp-Hirth gliders, a Klixon
automatic circuit breaker acts as a "Master switch". Pressing it in, turns it ON, while
pulling it out, turns it OFF. On most other types of gliders, "Master switch" is a
toggle switch. By turning the Master switch on, power is available for onboard
instruments.
4. Switch ON the FCU instrument with a toggle-pull switch on top right side of the FCU
instrument. FCU instrument must always be switched ON during flight so
that the pilot can monitor the status of the battery packs and receives warnings
about any critical issues.
5. A “Power Switch” is different from the “Master Switch”!
The "Power switch" is usually located below the instrument panel. On early LAK
gliders, "Power switch" is located on the right side of the cockpit, on more recent
LAK glider it is located on instrument panel. A red safety guard cover protects the
switch from being unintentionally turned ON.
The "Power Switch is similar in function as the ignition switch on combustion
powered aircraft! It is critical to understand that this switch is not a "Master switch"
or vice versa. While the "Power switch" is OFF, you cannot start the electric motor.

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Switching the "Power switch" ON activates the main contactor. It connects the FES
battery packs to the motor controller and supplies the system with high voltage.
The system is fully operational when the "Power switch" is ON.
6. The "Power switch" should be ON only during powered flight. After the
motor stops and the propeller aligns horizontally with the fuselage, turn OFF the
"Power switch", by pushing the red safety guard downwards.
7. All FES gliders come equipped with a safety "Canopy switch" from the factory. It
prevents to start the motor when the canopy is open.
8. Unplug the "Connecting cable" and turn OFF the BMS on each of the FES
battery packs after landing! This action ensures that the FES system is not
operational.
9. Perform the following actions in the order described, to start the electric motor:
1. Insert the "Connecting cable" in the front and rear FES battery pack before
the flight. This connects the batteries in series.
2. Switch the instrument's "Master switch" ON before the flight.
3. Switch ON the FCU instrument before the flight. The instrument must be
turned ON during the entire flight.
4. Close and lock the canopy.
5. Lift the red safety guard of the "Power switch" and turn it ON. The system
becomes operational.
6. Check that the propeller area is free of people or obstacles.
7. Gently rotate the throttle knob clockwise -> the motor starts.
10. "Power switch" must be switched OFF before an air tow or winch launch, in order
not to endanger the person attaching the towing rope to the glider!
11.Turn off the "Power switch" for aero-towing or winching!
12. Always land with “Power switch” turned OFF.

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2.1 Important voltages and temperatures
You should know and memorize the following significant values before the first flight:
-first “Low voltage, reduce power” message appears at 95 V
-second “Critical low voltage, stop FES motor” message appears at 90 V
Warning: Do not discharge the batteries below 90 V!
-max. allowed motor and controller temperature is 90°C, the first warning appears
at 70°C
-max. allowed battery pack temperature is 55°C, the first warning appears at 45°C
-level flight requires approximately 3000 RPM
-maximum motor RPM is 4700
-propeller brake requires at least 1500 RPM to work. Even without power, the
windmilling provides enough RPM in flight for the brake to work.
2.2 Preflight Test Run
Warning: Perform a short ground run with low RPM before the flight –as a
part of a preflight inspection.
Conduct a short motor run with low RPM, as part of a preflight inspection to check if the
system works reliably and correctly by following the next steps:
1. Remove the tail dolly.
2. Close the canopy. The motor cannot start with an open canopy.
3. Make sure that nobody is around the propeller. Call "Clear prop!" loudly, before
starting!
4. Check that the propeller brake works. It requires more than 1500RPM to activate.
For further details, please refer to the FES Flight manual, FES FCU instrument manual, FES
GEN2 battery pack manual, and others available on our FES dedicated website at
download section: http://www.front-electric-sustainer.com/download.php

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3. Available FES manuals
You can find a list of all available FES manuals in the FES system manual.
4. Technical data
Check FES Maintenance manual, FES Flight manual, FES Motor manuals, FES propeller
manuals etc. for detailed technical data.
5. FES drawings
Check FES Maintenance manual, FES Flight manual, FES Motor manuals for technical
drawings.
6. Maintenance
Required maintenance is described in the FES maintenance manual.
7. Repair and service
In case of a fault or damage(s), contact the FES manufacturer, LZ design d.o.o.
8. Revision history
October 2016
The initial release of the quick guide, version 1.0
November 2016
Additional info about DATA connectors, version 1.1
October 2019
Minor updates, version 1.2
May 2020
Proofreading, version 1.3