H2W technologies LCAM 5/15 Instrucciones de instalación y funcionamiento
OPERATION
&
SERVICE MANUAL
LCAM 5/15
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05403
TABLE OF CONTENTS
Introduction Page 4
Features Page 5
Application Note Page 6
Technical Specifications Page 8
Startup and Calibration Page 9
APPENDIX
Drawing, LCAM 5/15, Installation Page 15
Drawing, LCAM 5/15, Schematic, Installation Page 16
Drawing, LCAM 5/15, Printed Circuit Board Assembly, Amplifier Page 17
Drawing, LCAM 5/15, 2-Axis Baseplate Assembly Page 18
Drawing, LCAM 5/15, 4-Axis Baseplate Assembly Page 19
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05404
INTRODUCTION
The H2W Technologies LCAM 5/15 H bridge linear servo amplifier provides the optimum solution
for applications which require high current loop bandwidth, low radiated electrical noise and low
crossover distortion. This amplifier is constructed using surface mount technology and incorpo-
rates the latest in heat transfer technology which makes it one of the most powerful amplifiers for
a given form factor.
Typical applications are brushed DC permanent magnet motors and voice coil motors.
The LCAM 5/15 is configurable and can operate in the following modes:
1. Velocity mode for motors with tachometer feedback.
2. Current mode for torque mode operation.
A basic velocity mode servo loop for a brush type motor is shown in figure A. An external
controller commands a given velocity (RPM). The velocity loop summing amplifier compares this
command with the actual motor velocity, supplied by a DC tachometer on the motor shaft, and
produces an error voltage proportional to the difference between the actual and commanded
velocity.
The velocity error is used to command motor current in the inner servo-loop. The current loop
summing amplifier compares the command current (velocity error) with the actual current in the
motor and produces an error voltage proportional to the difference between the actual and
commanded current.
Finally, the current error signal is used to produce an output to drive the motor.
The velocity loop may be bypassed, and an external current command fed directly to the current
loop. In this case, the external command signal controls the torque of the motor, rather than the
velocity. This is known as current-mode operation.
Figure A - Velocity mode servo loop for a brush type motor
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05405
FEATURES
Ergonomic Design Easy access to connections, adjustments and test points.
SMT construction Provides ultra compact size, cost competitive package and high relia-
bility.
Bandwidth All servo amplifiers have a nominal 10 kHz current loop bandwidth
which varies with the motor inductance.
Linear output stage Provides high bandwidth, low noise and zero crossover distortion.
Multimode operation Velocity mode (tachometer feedback) and Current mode (torque) .
Operating Voltage Operating input voltage range: 24-75 VDC for standard LCAM 5/15
module.
Basic versions Velocity and current modes.
Fault protection Short from output to output, short from output to ground, amplifier
RMS over current, and amplifier over temperature.
Status indicator LEDs indicate status on the LCAM 5/15.
Dedicated inputs Command signals, +/- limits, inhibit, reset, and fault.
Dedicated outputs Fault out and motor current monitor.
Current limit Peak motor current is adjustable.
External fault reset An input is provided to reset the amplifier in the event of a fault.
CE compliant All servo amplifiers are CE marked.
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05406
APPLICATION NOTE
POWER DISSIPATION CONSIDERATIONS AND CALCULATIONS WHEN USING
LINEAR DC SERVO AMPLIFIERS:
When selecting a linear amplifier, the following ratings of the amplifier should be known in order to
properly size the amplifier to your system requirements:
1– The total wattage, peak current, and voltage rating of all the semiconductors installed on the
heat sink of the output power stage of the amplifier.
Output transistor ratings for the LCAM 5/15 series are:
Voltage: 250 Volts
Peak current: 60 A; Continuous current: 30 A (Normally shipped with 12-20A limit)
Total wattage @25 deg C.:1200 Watts
The LCAM 5/15 series amplifier is a module style amplifier requiring an external unregulated sin-
gle polarity DC power supply. H2W Technologies offers various unregulated power supplies for
the LCAM 5/15 series amplifiers.
The LCAM 5/15series amplifier is also available in multi-axis configurations. That is, there are
two basic baseplate assemblies namely 2-axis and 4-axis baseplate assemblies that have built-in
AC to DC power supplies (un-regulated) and cooling fans. The 2-axis baseplate assembly con-
tains one AC to DC power supply, one fan, and up to two LCAM 5/15 amplifier modules. The 4-
axis baseplate assembly contains one AC to DC power supply, two fan, and up to four LCAM 5/15
amplifier modules. For multi-axis applications, it is always recommended to use three phases
power transformers for minimizing ripple voltage during high current demand scenarios where all
axis motors are running at full load simultaneously. H2W Technologies offers various isolated
three phases power transformers.
2– Typical continuous internal rating of the amplifiers running at normal room conditions is:
LCAM 5/15 series; 250 Watts continuous
For most applications, the above heat sinking is adequate. However, if you have a usage mode
where the heat sink temperature becomes excessive, please contact H2W Technologies and we
can furnish a larger heat sink with greater air flow for your application.
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05407
Use the following relationships to calculate amplifier dissipation :
1) Pd = Im x Vb (watts)
Where: Pd = Total watts delivered from bus
Im = Motor current
Vb = Bus voltage
2) Pm = Im x Vm (watts)
Where: Pm = Total power (watts) dissipated in motor
Vm = Motor voltage
3) Pa =Im x Vb - Im x Vm
Where: Pa = Total watts dissipated at amplifier
From the above relationship, it can be surmised that the worst case dissipation occurs when the
amplifier has to deliver a high continuous current at a low motor speed, i.e., less motor BEMF and
more current. For some applications, a power resistor can be added in series with the motor thus
shifting some of the power dissipation from the amplifier to the resistor.
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05408
TECHNICAL SPECIFICATIONS
Output
LCAM 5/15: 15A peak, 5A continuous, (forced air cooling required)
Note: Large motor and Small motor versions have different velocity loop compensation.
Input
LCAM 5/15: 24-75VDC
Integral forced air fan cooling (multi-axis LCAM 5/15 only)
Analog command signals: differential & single ended, adjustable gain
Reset: LCAM 5/15: pull up/pull down, active high only
Inhibit: Same as Reset
+/- Limits: Same as Reset
Output Connections
Motor : MTR + & MTR-
Fault out: LCAM 5/15: Optically isolated can sink up to 50 mA, active high only
Bandwidth
10 kHz maximum and varies with motor inductance
Status Indicator
LCAM 5/15: Green Run LED, Red Inhibit LED, Red Fault LED
Mechanical
LCAM 5/15 module: Height: 7.13”, Width: 2.23”, Depth: 5.69”
LCAM 5/15 2-Axis: Height: 10.75”, Width: 9.75”, Depth: 6.93”
LCAM 5/15 4-Axis: Height: 10.75”, Width: 14.90”, Depth: 6.93”
Environmental
Operating temperature 0 to 55°C
Storage temperature -40 to 80°C
Humidity 5 – 95% relative (non-condensing)
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-05409
STARTUP AND CALIBRATION
This section contains the procedure required for initial start up and amplifier calibration. The
LCAM 5/15 series amplifier can be configured to run in velocity mode (x.x) and current mode
(y.y).
Required Equipment: Oscilloscope, voltmeter & battery box. The battery box serves as a step
input voltage command, applying and removing a flashlight battery can also be used for this
function.
Refer to the technical specifications page and the drawings in the appendix for the information
needed to supply the correct power and to wire the model you are starting up. An isolation trans-
former is needed for the multi-axis LCAM 5/15. An isolated power supply (unregulated is OK)
providing the necessary voltage is required for the LCAM 5/15 module. H2W can provide appro-
priate transformers and power supplies. Consult an H2W applications engineer or sales person
for assistance.
A. Initial Start Up:
When applying power to start up your amplifier system for the first time, we recommend you
follow this procedure. If you have already gone through this procedure you can skip to the
appropriate calibration procedure.
1. Check for any loose or damaged components.
2. Check that all connections are tight.
3. Be sure that the motor mechanism is clear of obstructions. If the mechanism has limited
motion, e.g: a lead-screw, set the mechanism to mid-position.
4. Disconnect the signal and auxiliary inputs.
5. Be sure the Loop-Gain pot(s) are fully CCW (RV6 for LCAM 5/15). This will prevent the motor
from running away in velocity mode when power is applied.
6. Check for the correct AC voltage before connecting to LCAM 5/15 multi-axis amplifier. The
DC Bus (amplifier supply-voltage) will be 1.4 times greater than the AC value. If the voltage is
correct, remove power and connect AC source to amplifier inputs. For the LCAM 5/15 module
amplifier, check for the correct DC voltage before connecting to the amplifier power input.
7. Work on only one amplifier axis at a time for LCAM 5/15 multi-axis amplifiers.
H2W Technologies, Inc., 26470 Ruether Ave. #102, Santa Clarita, CA 91350, U.S.A. (888) 702-054010
B. Calibration of the Velocity Mode Amplifier (LCAM 5/15 Series):
The amplifier, in this configuration, receives an analog, bi-polar input command which is
proportional to the motor velocity. The amplifier receives velocity feedback from a tachometer
which is usually mounted to the rear of the motor. The following pots will be set during calibration:
(Note: RV6 is a single turn pot and RV1-RV5 are 10-turn pots.)
PROCEDURE:
1. Apply main power and fan power. Visually confirm a green LED. Depending on the configura-
tion of the Inhibit, Reset and +/-Limits, it may be necessary to make appropriate connections
to those terminals before the amplifier will be enabled and energize the motor.
2. Slowly turn the Loop Gain (RV6) CW fully. Motor should be stopped or turning slowly. If the
motor starts running away, remove the power, reverse the tach leads, and retest.
3. Set Balance (RV2) for zero motor rotation.
4. Install a micro-shunt at J3 connector (across J3-1 to J3-2).
Note: For single-ended signal input amplifier, a micro-shunt is permanently installed at J3
connector. On the other hand, the micro-shunt should be removed for differential input amplifi-
er after the calibration process.
5. Connect oscilloscope to J1-7 (MTR I) and battery box to J1-1 (J1-4 is common for both). The
voltage on J1-7 is a function of motor current: 1V = 2.0A. While applying a step input voltage,
adjust Current Limit (RV5) for desired peak current.
The purpose of the following procedure is to set the system bandwidth to obtain a critically-
damped response or a one hook overshoot response with the maximum possible Tach. Gain.
There are many possible settings of Tach. Gain and Compensation which will yield the desired
waveform: The optimum setting will occur when Tach Gain is as CW as possible and
Compensation is as CCW as possible. However, the servo loop may become unstable (the
motor oscillates or hunts) with a very low (near CCW) setting of Compensation. In this case,
stability is the limiting factor: At no time should the servo-loop be allowed to be unstable.
Amplifiers are normally shipped with the Tach. Gain (RV4) set at 100%. This is a good place
to start. If you are unsure of where the Tach. Gain is set, turn the Tach Gain (RV4) fully CW
(up to 10 turns).
6. Connect oscilloscope to J1-3 (TACH IN) and J1-4 is common. Set battery box for a DC signal
output to obtain approximately 400RPM. The RPM may be set by measuring the tach voltage
at J1-3, e.g., 2.8VDC for a 7V/KRPM tach is 400RPM.
Pots Name of Pot Notes
RV1 Signal Gain, SIG Sets the input voltage to velocity ratio for signal input.
RV4 Tach Gain, TACH Sets the DC tachometer gain.
RV6 Loop Gain,
LOOP GAIN
Used to shut off uncalibrated amplifiers. When the loop gain is
fully CCW, no current is delivered to the motor.
RV2 Balance, BAL Used to null any offset in system.
RV3 Compensation, COMP Used in conjunction with tach. gain to set the system bandwidth.
RV5 Current Limit, I LIMIT Sets the maximum motor current. Shipped set CCW (min. current).
Este manual sirve para los siguientes modelos
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