Great Planes GPMG5115, GPMG5145 User Manual

Congratulations, you have just purchased the
Ammo 20mm power system components. All
the components are sold separately to allow
you to customize your power system to your
airplane.The components needed to assemble
your Ammo 20mm power system are: Ammo
20mm motors, a 20mm stick mount gearbox,
propeller, propeller adapters and brushless
speed control. This instruction sheet explains
how to determine what you will need and how
to assemble each component.

AMMO 20mm PO

AMMO 20mm PO

WER SYSTEM

WER SYSTEM

by Great Planes

®

Model Stock #

20-30-2650...............GPMG5115

20-30-3500...............GPMG5120

20-30-4300...............GPMG5125

20-30-5200...............GPMG5130

20-40-2080...............GPMG5135

20-40-3500...............GPMG5140

20-40-4850...............GPMG5145

The Ammo motors are labeled to provide the
most information at a glance.For example:the
20-40-4850kV is 20mm in diameter, 40mm
long and has a kV (rpm-per-volt) of 4850 rpm.

Motor Output Shaft
Diameter and Length: 2x10mm [0.08"x0.4"]

Weight (30mm): 45g [1.6oz.]
Weight (40mm): 65g [2.3oz.]

MOTORS

An ESC is basically the device that controls
your motor through your radio system. Never
run any Ammo motors with a brushed ESC. It
will not work and you may damage both the
motor and the ESC. Always use a brushless
ESC. ElectriFly offers two Silver Series
Brushless ESCs that will work with the Ammo
20mm motors.

ELECTRONIC SPEED CONTROL (ESC)

ElectriFly Silver Series 8 (SS-8) ESC

(GPMM1800)

for 8A maximum constant current draw.

These ESCs come with 2mm female bullet
connectors that plug directly into the 2mm
male connectors installed on the Ammo
20mm motors, so no soldering is required.
Also, these ESCs come with Micro Deans
battery connectors that match the connectors
that are found on most batteries they will use.

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ElectriFly Silver Series 12 (SS-12) ESC

(GPMM1810)

for 12A maximum constant current draw.

56.2mm

2.2mm

20mm

30mm

OR 40mm

16mm

11.8mm

2.5mm

MOUNTING

SCREW

GEARBOX

The ElectriFly Ammo motors have high kVs
meaning that they like to run at very high rpm.
A gear drive is used in order to reduce the rpm
allowing a larger, more efficient propeller to be
used. Great Planes ElectriFly offers a 20mm
Stick Mount Gear Drive (GPMG0500) with
several pinions that allow for the following
gear ratios:

Low Ratio> 4.5:1, 5.3:1, 6.4:1, 8:1 <High Ratio

If you use a prop that is too small with a gear
ratio that is too low, the motor will draw very
little current and the prop will turn at too low of
an rpm to produce any usable power. The
higher the gear ratio, the smaller the prop will
need to be and the higher the rpm will be. If the
gear ratio is too high for the prop used, the
motor will draw excessiv e current and ov erheat.
The included chart, on the inside of the header
card, shows the motor/prop/gear ratios that
have been tested and found to work well.

The Stick Mount Gear Drive is designed to fit
the 10mm motor mounting stick that is common
on most of today’s small park flyers.

1. Aluminum Gear Drive Body (1)

2. Aluminum Top Plate (1)

3. 2.5x20mm SHC Screw (2)

4. Prop Saver Hub (1)

5. Rubber O-Ring (1)

6. 2.5x4mm Machine Screw (2)

7. 2.5mm Flat Washer (2)

8. 64 T ooth Spur Gear (1)

9. 2.5x7mm Machine Screw (2)

PROPELLER ADAPTERS

The 20mm Stick Mount Gear Drive uses a
3mm prop adapter. If you will be using the
Ammo 20mm Motor without a gear drive it
requires a 2mm prop adapter.

GPMQ4930 3mm Set Screw Type

GPMQ4953 2mm Collet Type
GPMQ4959 3mm Collet Type

GPMQ4620 3mm Prop Saver

(Included with Gearbox)

PROPELLERS

There is a wide selection of propellers
available for electric use. The 20mm motors
use mainly low-power electric type props such
as the Great Planes PowerFlow
the APC Slo Flyer props. The larger the
propeller used, the more current your motor
will draw. The smaller the propeller, the less
current the motor will draw.

Shown are a few of the recommended electric
props. Due to the large range of propellers
and the constant addition of new sizes, visit
our web sites at www.electrifly.com and
www.greatplanes.com for the most up-to­date listing of electric type props.

GPMQ6655.......10x3.5S PowerFlow

GPMQ6660.......10x4.5S PowerFlow

GPMQ6695.......11x4.5S PowerFlow

APCQ5000..........8x3.8SF Slo-Flyer

APCQ5010..........9x4.7SF Slo-Flyer

APCQ5015........10x4.7SF Slo-Flyer

APCQ5016........10x3.8SF Slo-Flyer

APCQ5017........11x3.8SF Slo-Flyer

APCQ5020........11x4.7SF Slo-Flyer

APCQ5025........11x7SF Slo-Flyer

APCQ5026........12x6SF Slo-Flyer

APCQ5027........12x3.8SF Slo-Flyer

APCQ5028........12x8SF Slo-Flyer

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props and