wheeler WM540 User manual

User Manual
For
WM540
High Performance Microstepping Driver
Attention: Please read this manual carefully before using driver!
Changzhou Wheeler Motor Co., LTD
www.wheeler.com.cn
86-519-83252878 China
[email protected]
The content of this manual has been carefully prepared and is believed to accurate, but no responsibility is assumed for
inaccuracies.
All Rights Reserved

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WM540 High Performance Microstepping Driver
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Table of Contents
1. Introduction, Features and Applications ·································································2
2. Specifications and Operating Environment ····························································2
3. Driver Connectors P1 and P2 ·················································································3
4. Power Supply ········································································································.4
5. Driver Voltage and Current ····················································································4
6. Selecting Microstep Resolution and Driver Current ··············································5
7. Control Signal Connector (P1) Interface ································································6
8. Protection Features ·································································································8
9. Driver Connection to Motors ················································································ 8
10. Connection Diagram for Driver, Motor, Controller ··············································11
11. Control signal waveform and timing ·····································································11
1. Introduction, Features and Applications
WM540 Driver is a high performance microstepping driver based on the most advanced technology in the world today.
It is suitable for driving 2-phase and 4-phase hybrid step motors (current 4.0A). By using advanced bipolar constant-
current chopping technique, it can output more speed and power from the same motor, compared with traditional
technologies such as L/R drivers. Its current control technology allows coil currents to be accurately controlled, with
much less current ripple and motor heating than other drivers on the market.
Features of this driver
•High performance, low cost
•Supply voltage up to +45VDC*, current to 4.0A for WM540 Driver
•Inaudible 20khz chopping frequency
•TTL compatible and optically isolated input signals
•Automatic idle-current reduction
•Mixed-decay current control for less motor heating
•14 selectable resolutions in decimal and binary
•Microstep resolutions up to 25,000 steps/rev
•Suitable for 4,6,8 lead motors
•Over-current, over-voltage and short-circuit protection
•Small size (118 x 76 x 34mm)
Applications of this driver
Suitable for a wide range of stepping motors such as low voltage versions of sizes 11, 14, 17, 23, and usable for various
kinds of machines, such as X-Y tables, labeling machines, laser cutters, engraving machines, and pick-place devices,
particularly useful in applications with low noise, low vibration, high speed and high precision requirements.
2. Specifications and Operating Environment
Electric Specifications (Tj = 25℃)
WM540
Parameters Min Typical Max Remark
RMS Output Current 0.5A by user 4.0A By DIP switch
Supply voltage (DC) +20V +36V +45V *
Logic signal current 10mA 12mA 18mA
Pulse input frequency 0 By user 500Khz
Isolation resistance 500MΩ
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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Operating Environment and Parameters
Cooling Natural cooling or forced convection
Space Avoid dust, oil, frost and corrosive gas
Temperature 0°－ 50℃
Humidity 40 －90%RH
Environment
Vibration 5.9m/s2Max
Storge Temp. -20℃ － +65℃
Weight About 0.4kg/WM540
WM540 Front View
Figure 1: Mechanical Dimensions
3. Driver Connectors, P1 and P2
The following is a brief description of the two connectors of the driver. More detailed descriptions
of the pins and related issues are presented in section 4, 6, 8, 9.
Control Signal Connector P1-pins
Pin No. Signal Functions
1 Pul﹢(+5V)
2 Pul﹣(pulse)
Pulse signal: in single pulse(pulse/direction) mode, this input
represents pulse signal, effective for each upward – rising edge; in
double pulse mode (pulse/pulse) this input represents
clockwise(CW)pulse. For reliable response, pulse width should be
longer than 3υs.
3 Dir﹢(+5V) Direction signal: in single-pulse mode, this signal has
4 Dir﹣(Dir)
low/high voltage levels, representing two directions of motor
rotation; in double-pulse mode (set by inside jumper JMPI), this
signal is counter-clock (CCW) pulse,
effective on each rising edge. For reliable motion
response, direction signal should be sent to driver 2υs
before the first pulse of a motion direction reversal.
5 Ena+(+5V) Enable signal: this signal is used for enable/disable, high
6 Ena- (Ena)
level for enabling driver and low level for disabling driver.
Usually left unconnected(enabled).
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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Remark 1: Pul/dir is the default mode, under-cover jumper JMP1 can be used to switch toCW/CCW double-pulse mode.
Remark 2: Please note motion direction is also related to motor-driver wiring match. Exchanging the connection of
two wires for a coil to the driver will reverse motion direction. (for example, reconnecting motor A+ to driver A- and
motor A- to driver A+ will invert motion direction).
Power connector P2 pins
Pin No. Signal Functions
1 Gnd DC power ground
2 +V DC power supply, +24VDC －+72VDC*, Including
voltage fluctuation and EMF voltage.
3, 4 Phase A Motor coil A (leads A+ and A-)
5, 6 Phase B Motor coil B (leads B+ and B-)
4. Power supply Selection
It is important to choose appropriate power supply to make the driver operate properly.
Maximum Voltage Input:
The power Mosfet inside the driver can actually operate within +20V－+45VDC*, including power input fluctuation
and back EMF voltage generated by motor coils during motor shaft deceleration. Higher voltage will damage the driver.
Therefore, it is suggested to use power supplies with theoretical output voltage of no more than +45V, leaving room for
power line fluctuation and Back EMF.
Regulated or Unregulated power supply:
Both regulated and unregulated power supplies can be used to supply DC power to the driver. However, unregulated
power supplies are preferred due to their ability to withstand current surge. If a regulated power supply is used, it
should be a linear type.
Multiple drivers:
It is possible to have multiple drivers share one power supply to reduce cost, provided that the supply has enough
capacity. DO NOT dazy-chain the power supply input pins of the drivers(connect them to power supply separately) to
avoid cross interference. Higher supply voltage will allow higher motor speed to be achieved, at the price of more
noise and heating. If the motion speed requirement is low, it’s better to use lower supply voltage to improve noise,
heating and reliability. NEVER connect power and ground in the wrong polarity, it will damage the driver. NEVER
connect or disconnect the motor leads with power on to the driver.
5. Driver Voltage and Current Selection
This driver can operate small-medium size step motors (such as low voltage versions of sizes 11, 14, 17, 23) made by
Wheeler or other motor manufactures from around the world. To achieve good driving results, it is important to select
supply voltage and output current properly. Generally, supply voltage determines the high speed performance of the
motor,
● Selecting Supply Voltage:
Higher supply voltage can increase motor torque at higher speeds, thus helpful for avoiding losing steps. However,
higher voltage may cause more motor vibration at lower speed, and it may also cause over-voltage protection and even
driver damage. Therefore, it is suggested to choose only sufficiently high supply voltage for intended applications.
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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● Setting Proper Output Current
For a given motor, higher driver current will make the motor output more torque, but at the same time causes more
heating in the motor and driver. Therefore, output current is generally set to be such that the motor will not overheat for
long time operation. Since parallel and serial connections of motor coils will significantly change resulting inductance
and resistance, it is therefore important to set driver output current depending on motor phase current, motor leads and
connection methods. Phase current rating supplied by motor manufacturer is important to selecting driver current, but
the selection also depends on leads and connection:
6. Selecting Microstep Resolution and Driver Current Output
This driver uses an 8-bit DIP switch to set microstep resolution, dynamic current and standstill current, as shown below:
Current during motion Microstep resolution
● Microstep Resolution Selection
Microstep resolution is set by SW5, 6, 7, 8 of the DIP switch as shown in the following table:
Microstep Step/rev.(for 1.8°motor) SW5 SW6 SW7 SW8
2 400 OFF ON ON
ON
4 800 ON OFF ON
ON
8 1600 OFF OFF ON
ON
16 3200 ON ON OFF
ON
32 6400 OFF ON OFF
ON
64 12800 ON OFF OFF
ON
128 25600 OFF OFF OFF
ON
5 1000 ON ON ON OFF
10 2000 OFF ON ON OFF
20 4000 ON OFF ON OFF
25 5000 OFF OFF ON OFF
40 8000 ON ON OFF OFF
50 10000 OFF ON OFF OFF
100 20000 ON OFF OFF OFF
125 25000 OFF OFF OFF OFF
2 400 OFF ON ON
ON
● Current Setting
The first three bits (SW1, 2, 3) of the DIP switch are used to set the current during motion (dynamic current ), while
SW4 is used to select standstill current.
WM540 DIP Switch settings for RMS current during motion:
RMS Current
for WM540 SW1 SW2 SW3
1.5A on off off
1.9A off on off
2.3A on on off
2.7A off off on
3.1A on off on
3.5A off on on
4.0A on on on
Standstill Current (half/full)
1 2 3 4 5 6 7 8
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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Note that due to motor inductance the actual current in the coil may be smaller than the dynamic current settings,
particularly at higher speeds.
DIP setting for current during standstill:
SW4 is used for this purpose, the half current setting will reduce motor heating at standstill. OFF meaning that the
standstill current is set to be half of the dynamic current and ON meaning that standstill current is set to be the same as
dynamic current.
7. Control Signal Connector (P1) Interface
This driver uses differential inputs to increase noise immunity and interface flexibility. Single-ended control signals
from the indexer/controller can also be accepted by this interface. The input circuit has built-in high-speed opto -
coupler, and can accept signals in the format of line driver, open-collector, or PNP output. Line driver (differential)
signals are suggested for reliability. In the following figures, connections to open-collector and PNP signals are
illustrated and VCC = 5VDC. For other VCC voltages limit the current to 18mA maximum.
Examples: R=560ohms if VCC=12VDC
R=1.5Kohms if VCC=24VDC
Open-collector signal (common +)
Figure 2
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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Figure 3: Signal Interface
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* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

8
M540 High Performance Microstepping Driver
To a number of built-in protections features.
hen power s tion will be activated and power indicator LED will turn red.
rotection will be activated in case of short circuit between motor coil and ground.
rotection will be activated in case of excessive current (such as a short circuit) which may otherwise damage the
n: since there is no protection against power leads (﹢, ﹣) reversal, it is critical to make sure that power
er will b
WM ams illustrate connection to various kinds
Note that when two coils are parallell speed can be
only at
Connecting to 8-Lead Motors
lead mo tem designer in that they may be connected in series or parallel,
be used in applications where a higher torque at lower speeds is required.
W
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8. Protection Functions
improve reliability, the driver incorporates
a. Over-voltage protection
upply voltage exceeds +80VDC*, protec
upply voltage is lower than +18VDC, th
W
When power s e driver will not work properly.
b. Coil-ground Short Circuit Protection
P
c. Over-current Protection
P
driver.
Attentio
supply leads are correctly connected to driver. Otherwise, the driv e damaged instantly.
9. Driver Connection to Step Motors
45
ot
0 driver can drive 4, 6, 8 lead hybrid step motors. The following diagr
of m or leads:
Figure 4: Driver Connection to Step Motor
y connected, coil inductance is reduced by half and motor
significantly increased. Serial connection will lead to increased inductance and thus the motor can be run well
lower speeds.
9.1
8 tors offer a high degree of flexibility to the sys
ying a wide range of applications.thus satisf
Series Connection
A series motor configuration would typically
Because this configuration has the most inductance, the performance will start to degrade at higher speeds. Divide the
motor's unipolar (peak) current rating by 1.4 for the RMS current, or the motor's bipolar current rating is the RMS
current.
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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Parallel Connection
An 8 lead motor in a parallel configu ve higher torque at higher speeds.
ultiply the motor's unipolar (peak) current rating by 1.4 for the RMS current, or the motor's bipolar current rating is
9.2 Connection to 6
Like 8 lead stepping motors, 6 lead motors have two configurations available for high speed or high torque operation.
The highe ed because it uses one half of the motor’s inductor windings.
The highe e configuration, or full coil, use the full windings of the phases.
dings, hence, lower torque output.
ike the parallel connection of 8 lead motor, the torque output will be greater at higher speeds due to lower inductance.
referred to as half copper. In setting the driver output current use the motor's specified per
Figure 5: 8 Lead Motor Series Connections
ration, because of the lower inductance, will ha
M
the RMS current.
Figure 6: 8 Lead Motor Parallel Connections
-Lead Motors
r speed configuration, or half coil, is so describ
r torqu
Half Coil Configuration
As previously stated, the half coil configuration uses 50% of the motor phase win
L
This configuration is also
phase (or unipolar) current rating as the RMS current.
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.

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WM540 High Performance Microstepping Driver
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Full Coil Co uration
The full coil configuration o rque at lower speeds is
esired. This configuration is also referred to as full copper. Divide the motor's specified per phase (or unipolar) current
current.
9.3 Connection to 4-Lead Motors
lead motors are the least flexible but easiest to wire. Speed and torque will depend on winding inductance. In setting
the driver e current rating as the RMS current.
_
Figure 7: 6 Lead Half Coil (Higher Speed) Motor Connections
nfig
n a six lead motor should be used in applications where higher to
d
rating by 1.4 for the RMS
Figure 8: 6 Lead Full Coil (Higher Torque) Motor
4
output current, use the motors specified per phas
Figure 9: 4 Lead Motor Connections
* For the European Market – the maximum input voltage must be limited to 70VDC to comply with CE regulations.