Polarity E2K | Interactive Electronic Technical Manual

1. Manual Information & General Remarks

This service manual contains maintenance, troubleshooting, and assembly information for the Polarity Executive E2K electric smart bike.

Manufacturer: Polarity Smart Bikes (SJ Electric Vehicles Pvt Ltd)
Model: Executive E2K
Type: Electric Smart Bike (Pedal-assist with BLDC hub motor)

Important Notes:

All assembly operations, extensions, readjustments, modifications, or repairs must be carried out by qualified service personnel.
The electrical systems (battery, controller, motor) operate at high currents and pose potential safety hazards if mishandled.

2. Technical Specifications

Dimensions & Capacities

Kerb Weight: 55 kg
Payload Capacity: 110 kg
Dimensions: 1864 mm × 635 mm × 1016 mm
Seat Height: Adjustable, 635 mm to 645 mm

Performance & Motor

Motor Power: 1.5 kW Brushless DC (BLDC) Rear Hub Motor
Top Speed: 60 km/h
Range: 80 km+ per charge
Drive Type: Rear Hub Motor with pedal-assist (Chain Drive)

Battery & Charging

Battery Type: Removable/Portable Lithium-ion
Standard Charger (Home): 50V 5A (~250 W output)
Optional Fast Charger: 50V 10A (~500 W output)
Charging Time: Sub-2 hours (Standard), < 1 hour (Fast Charger)

3. Safety Instructions

Compliance with safety protocols is mandatory for all maintenance, diagnostic, and assembly procedures on the Polarity E2K smart bike.

Required Workshop PPE (ISO 7010 Compliant)

Insulated Gloves Class 0 (1000V DC Rated)

Eye Protection ANSI Z87.1 Impact Shield

ESD Safety Boots Non-Conductive Rubber Sole

Class D / CO₂ Extinguisher Within 3m of service bay

DANGER 50V DC High Voltage & Current Hazard

Touching live busbars or controller terminals will cause severe electrical shock, arc-flash, or fire. Always isolate power before service.

120s

System charged. Do not touch electrical components.

WARNING Mechanical Pinch & High Torque Point

BLDC hub motor delivers instant torque. Sudden engagement will cause entrapment in chain drive or brake rotor. Verify setup below:

Bike locked on Heavy-Duty Stand
Hands & tools clear of wheel/chain
Axle & caliper bolts torqued (60/10 Nm)

Verifying mechanical safety clearances...

CAUTION Thermal & Lithium-ion Battery Care

Lithium-ion cells are sensitive to shock and high heat. Damaged pack poses thermal runaway risk. Validate pack temperature:

5-Step Battery Isolation Protocol (Mandatory Before Service)

1

Power Off System Turn ignition key to KEY OFF position.

2

Secure Key Remove ignition key and keep in technician's pocket.

3

Disconnect Battery Unlock & unplug main high-current battery connector.

4

Capacitor Discharge Wait 120 seconds for MCU internal capacitors to drain.

5

Zero-Voltage Test Verify 0.0V DC at MCU input terminals with multimeter.

Pre-Service Technician Safety Sign-Off

Tap each safety requirement to acknowledge and confirm before commencing repair work:

✓ I am equipped with Class 0 Insulated Gloves (1000V) and Eye Protection.
✓ The vehicle is chocked and securely locked onto an approved workshop stand.
✓ Service area is dry, clear of flammable materials, and a CO₂ fire extinguisher is nearby.
✓ I have verified 50V Battery Disconnect is unplugged and key is in KEY OFF position.

4. Tools Required

Metric Allen Key Set

Sizes: 2.5mm to 10mm

Metric Wrenches

Sizes: 8mm to 19mm

Screwdrivers

Phillips & Flat-head

Digital Multimeter

Up to 100V DC & continuity

Torx Key Set

Star key set

Torque Wrench

Range: 5 Nm to 60 Nm

Spoke Wrench

For wheel tensioning

Chain Tool & Lube

Chain wear & servicing

5. Electronic Modules & Assembly

The electronic system of the E2K consists of the following primary modules:

Motor Controller (MCU)

Regulates power from the battery to the BLDC motor based on throttle and pedal-assist inputs.

⚡ Launch Simulator ↓

Battery Management System (BMS)

Integrated into the lithium-ion battery pack; monitors cell voltage, temperature, and balances charging.

Instrument Console

Digital/TFT display providing speed, battery level, range, and diagnostic information.

IoT Module

Handles GPS, Bluetooth, and mobile app integration.

Smart Ignition

Push-button start system replacing traditional keys for quick and secure power-on.

MCU Diagnostic Simulator

System logic validation & electrical signal routing — Polarity E2K

💡 Simulator Logic & Safety Purpose:

Real-time Signal Validation: Visually routes active power paths (green) and signal commands (orange) in real-time, helping technicians trace wiring routes without physical probes.
Brake Cut-off Overrides: Demonstrates the safety logic where squeezing the brake cuts all motor power instantly (status switches to REGEN), validating critical drivetrain failsafes.
Live IoT Integration: Supports streaming real-world telemetry packets from the bike using WebSockets, turning the manual into an active workshop diagnostic dashboard.

💡

How to use: Use the controls on the left to simulate different fault conditions. Watch how the Motor Controller responds and read the Telemetry Strip below for live values. Use the Scenario buttons below for guided fault tests.

Quick Test Scenarios:

State Legend: ⚪ IDLE — Powered, motor off 🟠 DRIVE — Motor outputting power 🔵 REGEN — Braking, energy recovery 🔴 FAULT — Motor disabled, check error code

Line Type Reference: DRIVE SIGNAL NO SIGNAL REGEN FLOW ↩ FAULT SIGNAL POWER / IGNITION ⚡ ↑ Reference samples only — live lines animate below

INPUT

Battery Pack

50.0 V

Simulate Low Volt (38V)

SWITCH

Smart Ignition

KEY OFF

Turn Ignition ON

INPUT

Throttle Input

0.0 V

0V (Idle) — 4V (Full)

SENSOR

Pedal-Assist (PAS)

INACTIVE

Simulate Pedaling

SWITCH

Brake Cut-off

RELEASED

Engage Brakes

IoT MODULE

IoT Telemetry

DISCONNECTED TRAINING

📍 GPS: — 📶 4G: — 📦 PKT: —

CONTROLLER

Motor Controller

MCU Module

STATE: IDLE

Input: 50.0V

100%

Current 0.0 A

RPM 0

Temp 32°C

INSTRUMENT CONSOLE

POLARITY E2K

0 km/h

MOTOR 1.5 kW BLDC Rear Hub Motor

INACTIVE

Current Draw 0.0 A

Motor RPM 0 RPM

Controller Temp 32 °C

Power Output 0 W

Battery SOC 100%

Range @ Load 80 km of 80 km+ max

6. Mechanical Assembly & Alignment

Brake Adjustment

Pad Alignment: Loosen the brake caliper mounting bolts slightly. Squeeze the brake lever firmly to center the pads over the rotor, then re-tighten the mounting bolts while holding the lever.
Cable Tension: Adjust the barrel adjuster at the brake lever to fine-tune pad clearance.
Rotor Inspection: Ensure the rotor is true. If rubbing occurs consistently at one spot, gently true the rotor using a truing fork.

Wheel Alignment & Chain Tension

Loosen Axle: Loosen the rear axle nuts.
Adjust Tension: Use the chain tensioner bolts on the dropouts to achieve approximately 15mm - 20mm of vertical play in the center of the chain.
Center Wheel: Ensure the wheel is perfectly centered in the swingarm.
Torque Spec: Tighten axle nuts to the specified torque.

7. Preventive Maintenance

Final Checkout Procedure

Device powers on without errors.
Throttle engages motor smoothly; pedal assist functions correctly.
Brakes stop the bike effectively and cut motor power.
All lights (headlight, taillight, indicators) operate normally.
No unusual grinding or clicking noises from the hub motor or bottom bracket.

8. Troubleshooting & Error Codes

The TFT console may display error codes if a fault is detected. Use the interactive Fault Diagnostic Simulator below to run guided diagnostics for each code.

💡 Diagnostic Isolation & Safety Purpose:

Visual Circuit Isolation: Selecting an error code immediately isolates the active fault circuit in pulsing red and dims unrelated components to 15% opacity to focus the technician's eyes on the problem area.
Interactive Checklist Sequence: Connects physical inspection checkpoints directly to progress tracking checkboxes on shop floor tablets.
Power-State Safety Cues: Dynamically shifts the Battery node illustration from green (energized for live tests) to dimmed grey (de-energized for continuity/resistance tests) to guide safety rules.

🔴 Fault Diagnostic Simulator

Select an error code to visualise the fault location and run guided diagnosis

Diagnostic Readout

No active faults detected. System is ready for troubleshooting.