NAVITAS PACKAGES AND CONVERSION KITS

Golf carts transport golfers, equipment and offer convenience in accomplishing daily activities. Latest innovations in modern carts show value for the user and the environment. Upgrading the control unit and converting the motor from DC to AC are some of the few emerging trends observed in the industry. These system upgrades require high-quality and compatible components commonly referred to as “Conversion Kits.” In this article, we’ll learn more about conversion kits from Navitas, the leading developer and manufacturer of electric vehicle control systems.

TERMINOLOGIES

In order to get a better understanding of the how's and why’s, here are some technical terms that we will encounter along the way with their definitions:

1. DC

DC is the abbreviation for direct current. This means that the electrical current is flowing in one direction.

About the motor:

A DC motor converts electrical energy to mechanical energy. Construction-wise, DC motors usually have brushes and a commutator, which limits speed control, requires maintenance, and shortens the life of the motor. The current of the armature windings is varied in order to control the motor speed. There is also a DC motor without brushes known as Brushless DC (BLDC) Motor, which is known for its improved efficiency and lifespan.

Types of DC Motor: Compound DC Motor, Permanent Magnet DC Motor, Series DC Motor, Shunt/Parallel DC Motor, and BLDC Motor

• DC Shunt Motor

Shunt Wound Motor has field windings in parallel connection with the armature winding. Compared to the armature current, the shunt field current is relatively lower because it has a higher number of turns. Also, the resistance is higher in the shunt field windings.

• A shunt wound DC motor is a constant-speed motor with reliable speed regulation capabilities.

• Although, the downside of utilizing this motor is that it slows down due to load increase
  

• DC Series Motor

Series Wound DC Motor has field windings and stator windings in a series connection. Due to this, the current of the armature is equal to the field current. The current flow is thicker since it is directly from the power supply causing an increase in the load-carrying capacity of the motor. This provides a high magnetic field that consequently produces very high torque.

• For a given power rating, the starting torque of this motor is the highest.

• Compared to a Compound and Shunt DC motor, a Series DC motor requires less power and current to deliver a high amount of torque
  

2. AC

AC is the abbreviation for alternating current. This means that the electrical current is switching back and forth changing its magnitude per period of time.

About the motor:

The alternating current drives the AC motor converting electrical energy to mechanical energy. In AC motors, frequency variation controls the motor speed. This motor offers brushless operation using the AC induction motor type, which is expected to last longer and requires low maintenance. An AC Motor with brushes is known as AC Synchronous Motor.

Types of AC Motor: AC Induction Motor and AC Synchronous Motor

3. Conversion Kit

The conversion kit is defined as a component or combination of components that are meant to convert an existing technology to the latest or to a much favourable version of the technology depending on the preference of the user.

4. Motor Controllers

Motor Controllers are used in regulating the operation of the motor. The functions of each controller differ from one another, but it mainly controls the torque and speed of the motor.

5. On-The-Fly Programmer (OTF Programming)

The term “on-the-fly” in programming is also defined as while running. This programming style allows live programming, controlling, or coding during run time. Using this programmer, there is no need to stop the vehicle and it can perform desired functions using real-time modification.

6. Navitas

Navitas Vehicle Systems Inc. specializes in the control systems and motors of electric vehicles. Navitas have developed controllers and accessories that are applicable to a wide range of vehicles utilized for both commercial and industrial purposes. Navitas also accommodates customization of controllers to fit the specification demand of the OEMs.

WHY UPGRADE CONTROLLERS

A controller controls and regulates motor speed as well as ensure the safety of the drivers, the passengers, and the bystanders. There are a number of reasons why a cart owner decides to switch controllers. Some of these reasons are as follows:

1. The stock controller is faulty.

2. A new controller may offer additional improvements in terms of performance quality.

3. A new controller may offer features that allow the controller to adapt to future technological trends (e.g. Allows remote system upgrades or downloadable features).

4. System upgrade may require changing the controller due to compatibility issues (e.g. DC to AC Motor Conversion).

5. Customer service or dealer-customer relationship is guaranteed upon purchasing the product (e.g. Manufacturers such as Navitas have a mobile application allowing the customer to report diagnosis).

WHY CONVERT YOUR MOTOR FROM DC TO AC

Golf carts have traditionally been on DC power, but a recent trend indicates that the manufacturers and users are converting their motors into AC induction since more advantages regarding performance lean towards AC motors. AC motors are deemed superior in the following performance indicators:

1. Longer Motor Life

DC motors have higher tendencies of wear and tear, which may require a series of maintenance and replacement over time. An AC motor lasts longer with fewer maintenance requirements.

2. High Performance in both Upward and Downward Slopes

A DC motor exhibits difficulty when going uphill and may have lower speed whereas, with AC motor, the vehicle can travel steadily exhibiting only a slight loss in speed even with heavier loads. For downhill control, an AC motor provides better control in navigation, speed, and brake accuracy. These differences in their performance are much more noticeable when navigating more than one hill.

3. Higher Torque

Compared to a DC motor, an AC motor generates higher torque allowing the vehicle to move at a steadier and faster pace. An AC motor also requires less power to reach a similar speed to a DC motor. Even when a faster speed is not required, an AC motor provides better overall performance.

Navitas takes pride in their DC to AC conversion kit due to the state-of-the-art design of the components that aim to improve the overall performance of the vehicle by improving its speed, efficiency, adaptability, and affordability.

PRODUCTS

NAVITAS DC TO AC CONVERSION KITS

Navitas offers several DC to AC conversion kits suitable for various electric vehicles. The following parts are included in the DC to AC conversion kits of Navitas. Each part can be sold separately or as a group. The parts included in the kit are as follows:

• TAC2 Controller

• TAC2 Module

• Mounting Kit

• On-The-Fly Programmer

• Induction Motor

• Cables

• Mounting Plate: E-Z-GO TXT Run/Tow Switch

• YAMAHA Ring Terminal for A2 Cable

NAVITAS DC AND AC CONTROLLER PACKAGES

Navitas has several DC and AC controller packages and each one is tailored to fit each vehicle. The list below indicates the parts included in the packages. Some packages may only include 2-3 parts from the list and some are exclusive only for specific carts.

The parts, diagrams, and their purpose are in the Appendix.

INSTALLATION OF NAVITAS DC/AC CONVERSION KIT

It is important to take note that each vehicle and its corresponding kit are different from each other. This installation guide includes general steps containing the basics, but some details should vary according to the cart and kit involved. A more detailed guide is available on Navitas’ website: https://www.navitasvs.com/manuals

1. Controller and On-The-Fly Programmer

1. Take out the stock controller. To do this, remove the cover to access its location.

2. Place the Navitas mounting plate and secure it using the provided holes. The screws that fit these holes are included in the mounting kit.

3. Remove the F1 and F2 cables of the DC motor.

4. On the back portion of the TAC2 controller, apply an adequate amount of thermal grease in order to seal the heatsink of both the cart and the controller allowing the heat to transfer from the controller. The controller is likely to run cooler when this method is applied.

5. Place the controller on the mounting plate.

6. Retrieve the run/tow switch from the stock housing and hook it up with the provided mounting plate in the kit, then place it beside the controller.

7. It is recommended to upgrade the solenoid as the stock solenoid may not be able to handle the demand.

8. Install the On-The-Fly programmer on the dashboard.

9. Plug the harnesses and secure the wiring according to the module provided.

2. Motor

1. Remove the DC motor by removing the cover plate. Carefully remove the positive and negative of the battery, take the bolts out, and lift the motor out from the compartment.

2. Gently place the AC induction motor and secure it with bolts.

3. Connect the motor wires.

4. Use insulator caps, if provided, to avoid electrical leaks and protect the motor.

5. Place the cover back on the vehicle.

6. Test the vehicle.

NAVITAS BLUETOOTH APP

How to use:

1. Install the controller to the cart

2. The vehicle should be turned On

• Some vehicles may require you to turn the Run/Tow switch On and some will require to turn On the Key Lock

3. On the app, connect to the controller. You may be required to be near the proximity of the vehicle.

4. To adjust settings, go to the Settings page and input the data as desired then press Save. The Settings page contains the following sections:

1. Speedometer Settings

2. Speed Limits

3. Input Thresholds

4. Advanced Options

5. Vehicle Direction

6. Off-Road Performance

7. Vehicle Information

5. To see the real-time graphs of the vehicle's activity, Go to the Settings page, go to the Vehicle Information section, then toggle the buttons of the parameters you want to view. To run the data log, press the Start button on the upper right corner of the screen.

• The data cannot be saved, but it can be shared with the Navitas team by just clicking the Cloud button located beside the Start/Stop button

6. To view the state of the vehicle, go to the Dashboard of the app.

APPENDIX

APPENDIX A: LIST OF PARTS

1. The TAC2 and TSX3.0 Controllers

The TAC2 and TSX3.0 Controllers are power MOSFET, fully-programmable technology that has an output capability of up to 600 amperes. Regenerative braking, speed limiting, and anti-rollback protection are some of the key features both controllers have. It can also communicate with other Bluetooth, RS232, and CAN Bus-enabled devices. This communication ability allows the user to remotely and virtually change the settings of the vehicle.

Controller Module:

The controller module contains a wiring diagram and the controller parts. The module may also include information about the harness and the revision history of the product. The module in each kit is different. The vehicle model, stock controller, and, in some cases, the throttle type are some of the content bases for each module.

TAC2 Controller Features:

1. Ability

1. A voltage-controlled power MOSFET device

2. Has the ability to recapture the kinetic energy through recharge. This is possible due to Regenerative Braking functions

3. Has the ability to restrict the speed of the vehicle to ensure safety from exceeding the speed limit. This feature is called Speed-limiting.

4. Allows A/B Speed Sensor Inputs

2. Adaptability

1. Lightweight

2. Compact Design

3. Dust Resistant (determined by Ingress Protection rating of IP5X)

4. Multiple Mounting Options

5. Easy to Install

3. Safety

1. Thermal, Undervoltage, and Rollback Protection

TSX3.0 Controller Features:

The TSX3.0 and TAC2 controllers have a similar list of features. However, the TSX3.0 has one additional feature.

• Additional Feature/s:

• Has the ability to reverse the DC motor without a contractor in order to improve the performance of the motor.

2. On-The-Fly Programmer

The on-the-fly (OTF) programmer has 5 parts—3 switch knobs, a key lock, and an LED light indicator

• Switches: The switch knobs are for Speed, Regen, and Acceleration.

• The SPEED switch functions as a speed and range controller. When limiting the speed to a lower rate, the vehicle will have a longer runtime.

• The REGEN switch allows braking control both for safety and its recharging capabilities.

• The ACCEL switch allows acceleration control to ensure that the vehicle is safe from sudden unintended acceleration.

• Key Lock: A safety feature that ensures that the car rejects input unless unlocked.

• LED Light: Indicates the condition of the vehicle providing system diagnostics to alert the driver.

3. Mounting Kit

The provided aluminum mounting plate in the Navitas conversion kit is designed to fit right to the location of the stock controller.

Hardware

The kit comes with the necessary screws needed for installation.

4. AC Induction Motor

The AC motor provided in the kit is a premium AC induction motor built with high-quality material and reliable construction. It is equipped with a speed and temperature sensor and is capable of providing high speed and torque. Each kit has different motor specifications suited for compatibility with the rest of the system. Club Cars use 10 Spline motors while Yamaha, E-Z-GO, and Star EV carts utilize 19 Spline motors.

Specifications of Available Motor:

5. Cables

Motor Sensor Cable

The Motor Sensor Cable is responsible for data transmission from the sensor to the control unit. The cable included in the kit transmits the temperature and speed of the motor.

Dimensions (inch):

AC Motor Phase Cable

This motor cable is used for the ‘W’ terminal. The existing cables A1 and A2 are for terminals U and V, respectively.

Dimensions (inch):

6. Battery Cable (only for RXV and Yamaha Drive2 YDRE2)

This battery cable connects the B- from the battery and B+ from the solenoid. The E-Z-GO Lithium Elite Series is not a compatible battery with this cable.

Dimensions (inch):

7. Resistor Wiring (only for RXV23)

This resistor wire serves as a replacement for one of the existing wires. In terms of length, the wire included in the kit is longer than stock wiring.

Dimensions (inch):

8. Mounting Plate of the Run/Tow Switch (only for E-Z-GO TXT)

The mounting plate is used to fasten the stock Run/Tow switch near the controller. This mounting plate is included in the kit.

9. Ring Terminal (only for YAMAHA)

A ring terminal is provided in the kit and it is used for A2 wire. The ring terminal is crimped to the A2 cable.

10. TSX Harness (for DC Motor)

The TSX harness included in the package varies according to the vehicle and its specifications. The vehicles with TSX harnesses are as follows:

• E-Z-GO

Models:

• TXT

• TXT PDS 36V with Curtis 1206MX

• TXT DCS 36V with Curtis 1206

• E-Z-GO with Curtis 1268/1520

• Yamaha

Models:

• G19

• G22

• Drive YDRE G29 with Moric

• STAR EV, Classic 36V Model

• Columbia, Par Car with Sevcon Controller

• Non-E-Z-GO with Curtis 1268/1520

• Club Car with Curtis 1510/1515