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ALPHA6700S Series Special AC Drive for Machine Tool

ALPHA6700S series is a new generation special AC drive for machine tool industry. Considering that rough machining has large cutting depth calling for high & stable start torque for main spindle and that finishing machining requires even torque, stable speed, and quick start/stop, ALPHA 6700S, with its rich application experience in machine tool industry and advantages of ALPHA6000S hardware, commendably satisfies these professional requirements of high start torque and strong capability of heavy load at high frequency.

Technical Characteristics

More precise motor model; large start torque; higher load capacity at high frequency

Control of high-frequency field weakening (for milling machine); stable current when frequency higher than 60Hz

Quick start, stop and brake

Steady-state speed precision keeps 5% with 0~180% load, meeting demands of machine tools
Lower speed fluctuation under heavy load; rapider torque response

Special design for machine tool industry; fixed key running parameters; reduced codes testing
Impressively reduce the spindle stalling

Precise model and algorithm; quick voltage rise; stable current; stable torque

100% slip compensation; once the load increases, the frequency is compensated to avoid severe speed fluctuation

Slip compensation filter time is 1.00s; vibration-free under heavy load at low frequency; 0.2s rapid frequency compensation under heavy load at high frequency

Optimized motor parameters of all power range; vectorized motor parameters with only 5% error; more precise model


The special AC drive gives a wide range of applications, including the numerical control machine tools, NC lathes, face miller, engraving machines, cold heading machines, mechanical presses, hydraulic machines, electric screw presses, rolling mills, planer-type milling machines, grinding machines, punch presses, boring machines, drilling machines, plate shearing machines, NC cutting tools, and more.

Technical Specifications of ALPHA6700S

Item Specification
Power Range 380V ±20% three phases: from 1.5 to 18.5kW
Rated Input Voltage and Frequency Three phases: 50/60Hz
Allowable Input Voltage Range 380V three phases: from 304 to 456V, Voltage unbalance rate of less than 3%, Frequency fluctuation of below ±5%
Rated Output Voltage From 0 to rated input voltage
Max. Overload Current G model: 150% for one minute, 180% for 20 seconds
Control Method V/F control, Open loop vector control
Frequency Range From 0.00 to 650.00Hz (from 31R5GB to 3004GB)
From 0.00 to 400.00Hz (from 35R5GB to 3018G)
Frequency Accuracy Digital command ± 0.01% (from -10℃ to +40℃)
Simulation command ± 0.01% (25℃ ± 10℃)
Preset Frequency Resolution Digital command 0.01Hz
Simulation command 1/1000 of the maximum frequency
Output Frequency Resolution 0.01Hz
Preset Frequency Signal From 0 to 10V, from 0 to 20mA
Acceleration-Deceleration Time From 0.1 to 3600 seconds (The acceleration and deceleration time are set individually.)
Braking Torque The additional braking resistance can reach up to 125%.
Voltage-Frequency Characteristics Four kinds of fixed V/F characteristics are optional.
Any V/F characteristic can be preset.
The V/F control with PG is available.
Protective Functions Over-voltage, under-voltage, current limit, over-current, overload, electronic thermal relay, overheating, over-voltage stall, load short circuit, grounding, under-voltage protection, input phase loss, output phase loss, short circuit to ground, interphase short circuit, motor overload protection, and more
Ambient Temperature From -10℃ to +40℃
Humidity From 5 to 95% RH (No condensation)
Storage Temperature From -40℃ to +70℃
Service Place Indoor (without any corrosive gas)
Installation Site The altitude is at most 1,000m. No dust, corrosive gas, or direct solar radiation can be found.
Vibration Less than 5.9m/s2 (0.6g)
Protection Rating IP20
Cooling Method Natural cooling or forced air cooling

ALPHA 6700S Selection Table

Voltage Classes Model Motor Power (kW) Rated Output Current (A)
380V Three Phases 6700S-31R5GB 1.5 4
6700S-32R2GB 2.2 6
6700S-3004GB 4 9
6700S-35R5GB 5.5 13
6700S-37R5GB 7.5 17
6700S-3011GB 11 25
6700S-3015GB 15 32
6700S-3018G 18.5 37

Overall Dimension of ALPHA6700S Series Special AC Drive for Machine Tool

Model H H1 W W1 D D1 D2 D3 d
6700S-31R5GB 180 169 115 105 150 158 85 120 4.5
6700S-3004GB 195 173 130 108 157 167 100 130 4.5

Model H H1 W W1 D D1 D2 d
6700S-35R5GB 270 255 190 175 176 186 122 7

Model H H1 W W1 D D1 D2 d d 1
6700S-3011GB/3015PB 373 360 235 200 176 188 125 7 12
6700S-3018G/3022P 420 405 270 200 218 230 175 7 14
Instruction Manual

Related Names
CNC Machine Tool Drive | Frequency Changer | Industrial Drives

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