NOVAK GT7 PROGRAMMABLE RACING ESC Specifications

INSTRUCTION MANUAL

Part #1785

STEP 3

SPECIFICATIONS

PRECAUTIONS

OPTIONAL ACCESSORIES

Input Voltage

4-6 cells

 (1.2 volts DC/cell)

Motor Limit

None

Case Width

1.37 inches

[3.48 cm]

Case Depth

1.11 inches

[2.82 cm]

Case Height

0.66 inch

[1.68 cm]

Weight 

(w/o wires)

0.93 ounce

[26.26 g]

On-Resistance 

@ Transistors

0.00058 

Ω

Rated Drive Current

640 amps

Rated Braking  Current

160 amps

BEC Voltage

6.0 volts DC

BEC Current

3.0 amps

Wire Length 

(Battery/Motor)

9 inches

[22.86 cm]

Signal Harness 

(replaceable)

9 inches

[22.86 cm]

Throttle Programs

7 

(6 fixed/1 adjustable)

Drive Profiles

1 of 5 

(in Program 7)

Brake Profiles

1 of 5 

(in Program 7)

Minimum Brake

 (all Programs)

1 of 7 

(20-55%)

PWM Frequency

1-23 kHz

@ 25

°

C transistor

junction temp.

POWER CAPACITORS  [#5675]

An external power capacitor is included, and MUST BE USED

to maintain cool and smooth operation. Refer to Step 3

Replacement Power Capacitor is  available in Novak kit #5675.

SCHOTTKY DIODES  [#5640]

The GT7 requires an external Schottky diode on the motor. The

external Schottky diode optimizes the speed control’s braking

and motor performance. Refer to Step 3

Additional Schottky diodes are available in Novak kit #5640.

MOTOR CAPACITORS  [#5620]

Additional motor capacitors are available in Novak kit #5620.

BATTERY/MOTOR 14G POWER WIRE  [#5500 & 5505]

Replacement GT7 power wire is available in Novak kits #5500

(36”red & 36”black) & #5505 (36”red & 36”blue).

INPUT SIGNAL HARNESS  [#5315 & 5320]

The user-replaceable input signal harness is available in both

short (4.5”) and long (9.0”) lengths to fit different applications.

4.5” harness in Novak kit #5315, and 9.0” harness in kit #5320.

GT7 REPLACEMENT TRANSLUCENT CASE  [#5680]

Replacement GT7 case is available in Novak kit #5680, and

includes the slide-mount Power Capacitor brackets.

• WATER & ELECTRONICS DON’T MIX!  Never allow

water, moisture, or other foreign materials to get inside

the speed control or on the PC Board.

• 4 TO 6 CELLS ONLY  Never use fewer than 4 or more

than 6 cells (7.2 volts DC) in the main battery pack.

• POWER CAPACITOR REQUIRED  An external power

capacitor is supplied, and MUST be used with your GT7.

Failure to use Power Capacitor will damage speed control

and void the warranty!

• SCHOTTKY DIODE REQUIRED  An external Schottky

diode is supplied, and MUST be properly installed on every

motor to reduce radio interference and obtain the best

performance and efficiency from your GT7.

• NO REVERSE VOLTAGE!  Reverse battery polarity can

damage speed control––Disconnect battery immediately.

• DISCONNECT BATTERIES WHEN NOT IN USE  Always

disconnect the battery pack from the speed control when

not in use to avoid short circuits and possible fire hazard.

• TRANSMITTER ON FIRST  Always turn on the power of

your transmitter first so that you will have control of the

radio equipment when you turn on the speed control.

• INSULATE WIRES  Always insulate exposed wiring with

heat shrink tubing to prevent short circuits.

• NO SOLVENTS  Exposing the speed control’s case to any

type of solvents will damage the plastic.

1. MOTOR CAPACITORS

Electric motors generate RF noise that causes interference.

The included 0.1

µ

F (50V) non-polarized, ceramic capacitors

must be installed on every motor to help reduce the

motor noise and also to prevent possible ESC damage.

Note: Some motors come with capacitors built-in. If your motor

only has two capacitors, you only need to install the capacitor

between the positive & negative motor tabs.

Solder 0.1

µ

F (50V) capacitors between:

• POSITIVE (+) motor tab & NEGATIVE (–) motor tab.

• POSITIVE (+) motor tab & GROUND tab*.

• NEGATIVE (–) motor tab & GROUND tab*.

*If motor has no ground tab, solder the capacitors to motor can.

Negative (–) motor tab

0.1

µ

F Capacitors

Schottky diode

Positive (+) motor tab

Ground / motor can

Extra 0.1

µ

F capacitors are available in Novak kit #5620.

2. INSTALL SCHOTTKY DIODE

• Solder the lead CLOSEST to the silver stripe on the body

of the Schottky diode to the POSITIVE (+) motor tab.

• Solder the lead OPPOSITE the silver stripe on the body

of the Schottky to the NEGATIVE (–) motor tab.

If Schottky diode is installed backwards it will be destroyed. Replace

only with Schottky diodes with a minimum rating of 35 volts/8 amps.

Schottky diodes are available in Novak kit #5640.

3. INSTALL POWER CAPACITOR

 (see Set-Up Photo & Fig. 4)

WHY POWER CAPACITOR IS NEEDED: 

The Power Capacitor

drops ESC operating temperatures by 10-15

°

F and dissipates noise

& voltage spikes from the ESC’s high switching speed. You MUST

use Novak capacitors, because other capacitors with similar ratings

will not provide the same protection. We have done extensive

research to find capacitors with the very best Quality Factors.

• Mount Power Capacitor using the included slide

bracket––insert bracket into one of the channels on

the side of the GT7’s case, and secure with the included

tie-wraps. Otherwise, mount Power Capacitor using

the included double-sided tape in desired position.

• Bend Power Capacitor’s leads flat along the top of the

capacitor in the direction of the PowerCap wires

coming out of the right side of the GT7’s case.

• Insulate capacitor’s leads with the included vinyl tubing

and heat shrink as shown in Figure 4.

• Solder capacitor’s NEGATIVE (–) lead 

{shorter lead on

capacitor}

 to the GT7’s BLACK PowerCap wire.

• Solder capacitor’s POSITIVE (+) lead to RED PowerCap wire.

4. CONNECT SPEED CONTROL TO RECEIVER

Configure input harness wires and connect ESC to the

THROTTLE CHANNEL of receiver as described in Step 1.

STEP 1

The GT7 speed control comes with the industry standard

connector on a user-replaceable input harness. This connector

works with all major radio brands. However, with some older

style receivers, the wiring sequence in the plastic connector

must be changed. This is an important step, because the

receiver electronics may be damaged if the sequence is incorrect.

JR • Hitec • Futaba • New KO • Airtronics Z

JR, Hitec, Futaba, new KO, & Airtronics Z receivers do not

need to have the ESC’s input harness wire sequence changed.

New Airtronics Z receivers have blue plastic cases & new KO

cases have tabs on the input harness openings as in Figure 1.

• Insert one end of the input harness into receiver with the

BLACK wire toward the outside edge of receiver case.

• Insert opposite end of input harness into ESC with the

WHITE wire toward the ‘S’ (signal) marking in the ESC’s case.

Old-style KO • Old-style Sanwa/Airtronics

If your receiver is an older KO or Sanwa/Airtronics, you must

change the sequence of the ESC’s input harness wires.

Old Sanwa/Airtronics cases are black in color & Old KO cases

do not have the tab openings, as in Figure 2 above.

• Insert one end of input harness into ESC with the WHITE

wire toward the ‘S’ (signal) marking in the ESC’s case.

• Interchange the red and black wires in the plug plastic at

the opposite end of the input harness as in Figure 3 below.

• Insert modified end of the harness into the receiver with

the RED wire toward the outside edge of receiver case.

FIGURE 3

With a small standard screwdriver, gently lift plastic

prong until wire and metal socket easily slide out of plastic housing.

1. DETERMINE BEST ESC MOUNTING LOCATION

Choose a mounting position that keeps power wires away

from the receiver and antenna, and will provide

maximum airflow around case to allow for proper cooling.

The GT7 has slide mount channels in each side of the

case for holding the ON/OFF switch & power capacitor.

This lets you to put the power capacitor on one side of ESC, while

positioning ON/OFF switch facing up, down, forward, or back on

the opposite side. The switch also has a hole in it for attaching with a

4-40 or smaller screw, or you can use the included double-sided tape.

2. SLIDE-MOUNT POWER CAPACITOR

To use the included slide bracket to mount the capacitor on the side

of the ESC, be sure you have enough space in the desired location.

Slide the bracket into one of the channels on the ESC

(start at the bottom and slide up into the channel)

. Secure the

capacitor to the bracket with the included tie-wraps.

3. INSTALL THE SPEED CONTROL & SWITCH

If desired, slide the switch into one of the channels on the

side of the ESC as described above for the power capacitor.

Mount the ESC using the included double-sided tape.

4. INSTALL THE RECEIVER AND ANTENNA

Mount receiver as far from ESC, motor, power wires,

battery, and servo as possible. These components all emit

RF noise when throttle is being applied. On graphite or

aluminum, it may help to place receiver on edge with

crystal and antenna as far above chassis as possible.

Note:  Mount the antenna as close to the receiver as possible, and trail

any excess wire off the top of the antenna mast––cutting or coiling the

excess antenna wire will greatly reduce radio range.

FIGURE 1

FIGURE 2

New KO (with tabs)

Old KO (no tabs)

tabs

no tabs

black

red

red

white

black

white

STEP 2

slide-mount

switch

power

capacitor

tie-wrapped

to bracket

solder tabs

slide

brackets up

into channel

heat shrink & vinyl tubing

to insulate leads

5. CONNECT SPEED CONTROL TO BATTERY PACK

• Cut GT7’s BLACK power wire to desired length and strip

1/8-1/4” of insulation off the end. Solder to battery

NEGATIVE (–) of a charged 4 to 6 cell pack.

• Cut RED power wire to desired length 

(so it will go from GT7,

to battery positive, then to motor positive)

 and strip 1/8-1/4”

of insulation off the end. Then strip a 1/4-3/8” section

of insulation from the mid-section of the wire where it

will attach to battery positive. The stripped mid-section

gets soldered to battery POSITIVE (+) [see Set-Up Photo]

6. CONNECT SPEED CONTROL TO MOTOR

• Take the stripped end of the RED power wire and solder

to the POSITIVE (+) motor tab.

• Cut GT7’s BLUE power wire to desired length and strip

1/8-1/4” of insulation of the end. Solder to the

NEGATIVE (–) motor tab.

TIP:  Twisting BLUE & RED wires once or twice around each other as

they go to the motor helps reduce RF noise emitted from power wires.

REPLACING POWER WIRES AT SPEED CONTROL

• Remove power wires at the PCB (printed circuit board), by

first removing ESC from the model so that you have access

to the bottom side of the solder tabs. Use a soldering iron

to apply heat to the power wire’s solder joint on the

bottom side of the solder tab, while gently pulling up on

the wire to remove it from the hole in the PCB.

• Replace power wires by stripping 1/8-1/4” of insulation

from the end of new wire. Tightly twist strands of wire,

and insert into proper solder tab’s hole. Use soldering iron

to apply heat to exposed wire that is extending past

bottom of PCB, and begin adding solder to tip of soldering

iron and to wire. Add just enough solder to form a clean

& continuous joint from the plated area of solder tab up

onto the wire. Using side cutters, trim remaining

 (now soldered)

wire from below the solder tab––about 1/16” above PCB.

IMPORTANT NOTE:  DO NOT OVERHEAT SOLDER TABS

Prolonged/excessive heating of solder tabs will damage PCB.

USING PLUGS FOR BATTERY & MOTOR CONNECTION

High-quality/low-resistance connectors, such as Dean’s Ultra

Plugs, can also be used to connect motor and battery.

Note: While plugs make component changes quick and easy, they

will never have as low of resistance as a good solder joint.

Use connectors that can not be connected backwards!

It is good practice to use female connectors on battery packs

to avoid shorting the connector and the battery.

If using connectors for both battery & motor:

Use a male connector on the ESC wires going to the battery

and a female connector on the wires going to the motor.

This will help prevent cross connection of the battery and motor

outputs that would cause internal damage to the ESC.

For additional information on using connectors, please visit our website.

GT7 BASIC SET-UP

CHANGING INPUT HARNESS

GT7 BASIC SET-UP

MOUNTING INSTRUCTIONS

GT7 BASIC SET-UP

HOOK-UP INSTRUCTIONS

PROGRAMMABLE

RACING ESC

The Novak Designers asked themselves: How do we

make a great speed control like the Cyclone even better?

First, we made it 30% smaller, 30% lighter, increased the

number of factory-installed Programs to 7, and eliminated

the need for an external programming device for customizing

the user-adjustable Program.

Next, we broke down the user-adjustable program into

separate Drive and Braking Profiles to allow the user to fine

tune the throttle response with a choice of 5 Drive Profiles,

5 Brake Profiles, 2 styles of braking, and 7 Minimum Brake

settings. Not only that, but each of the 7 Throttle Programs

stores its own Minimum Brake setting.

Add to that Novak’s new Variable Throttle Step Technology,

which delivers up to 1300 discrete steps for both drive and

braking, and you’ve got the smoothest speed control

available––no matter what frequency you select (1-23kHz).

Slide-mount

ON/OFF

switch

Power Capacitor

tie-wrapped to

slide-mount bracket

One-Touch/“SET”

programming button

Keep receiver & antenna

as far from motor, servo,

battery, & power wires

as possible.

User-replaceable

input signal

harness

Black power wire

(battery negative)

Status LEDs

Trail excess

wire off top

of antenna

mast

Red power wire

(battery &

motor positive)

Blue power wire

(motor negative)

Schottky

diode

Three 0.1

µ

F (50V)

ceramic capacitors

PowerCap wires

(–)

(+)

(–)

(+)

4 to 6 cell

battery pack

Status LEDs:

Yellow LED

Blue LED

Green LED

Red LED

SET

-UP PHOTO

FIGURE 4