Advanced Motion Controls

Note:

This FAQ addresses questions regarding the Analog product line and accessories. If you have a question regarding a Digital drive please see the digital support section or contact technical support.

Selection:

1. What basic steps should I take in selecting a motor and amplifier and power supply?

a. For an overview of analog amplifier and digital drive selection, see our Selection Guide.

2. Is it possible to get copies of UL/CE approval certificates?

a. Yes. A list of UL, UL Canada), and CE approved products can be downloaded and printed from our engineering reference page. Or, AMC can send copies of the approval certificates or UL yellow cards upon request. If you require these documents, please contact our technical support services at 805-389-1935 or complete the technical support contact form.

3. Is it safe to use a DC power supply voltage higher than the voltage rating specified for the motor?

a. Normally this is not a problem as long as the motor operates within the speed and current limits set by the manufacturer. Since motor speed is proportional to the voltage across the motor leads, select a power supply voltage that could not cause a mechanical over-speed in the event of an amplifier malfunction or a runaway condition.

Furthermore, always ensure the motor meets the minimum load inductance requirements of the amplifier and make sure the current limit is set to less than or equal to the rating of the motor.

4. How do I select the proper power supply rating for my application?

a. It is recommended to select a power supply voltage that is about 10 to 50% higher than the maximum required voltage for the application. This percentage is to account for the variances in K_t, K_e, and losses in the system external to the amplifier.

b. The current rating of the amplifier should be high enough to deliver enough power for the application. Remember that the equivalent output voltage of the amplifier is not the same as the supply voltage, therefore the amplifier output current will not be the same as the current from the power supply. To determine the appropriate current rating for the power supply, calculate total power required by the application and add 5%. Divide this power requirement by the supply voltage (I = P/V) to find the required current.

Click here for more detailed power supply selection information.

5. How much voltage ripple should I expect from an unregulated DC supply?

a. A formula for determining the approximate amount of ripple on an unregulated supply is:

V_ripple = I_ps * 0.007 / C

Where: V_ripple = peak-to-peak magnitude of voltage ripple

I_ps = current delivered to amplifier from power supply

C = power supply bus capacitance in Farads (F)

6. How can I determine the magnitude of regenerated voltage?

a. During motor deceleration or downward motion of the motor load, conversion of the system's mechanical energy (kinetic and potential) will be transformed to electrical energy on the supply bus. This energy is stored in bus capacitors as voltage. Download the Power Supply Selection Guide information sheet to calculate regeneration effects on your system.

7. Can I use a 12V bus supply with an Advanced Motion Controls amplifier?

a. No. The minimum turn-on voltage for Advanced Motion Controls amplifiers is 20V.

8. Does AMC provide mating connectors? What mating connectors do I need to use?

a. Advanced Motion Controls supplies one (1) of the following connectors with each drive, as required:

Type/Manufacturer	Number of Pins	Manufacturer’s Part Number
Straight, multi-pinMfg: Molexwww.molex.comPhone: 800-78-MOLEX	16	Plastic Body: 22-01-3167Insert Terminals: 08-50-0114
	5	Plastic Body: 22-01-3057Insert Terminals: 08-50-0114
Straight, Multi-pin (power/motor)Mfg: AMPwww.amp.comPhone: 800-522-6752	6	Plastic Body: 770849-6Insert Terminals: 770522-1
Screw-terminal, Quick DisconnectMfg: Phoenixwww.phoenixcon.comPhone: 800-888-1388	3	Part number: 1757022
	5	Part number: 1757048
	6(45°)	Part number: 1826322

b. AMC uses industry-standard connectors on all stock catalog amplifiers. The following connector styles can be purchased from most major electronics supply distributors (i.e. Digi-Key, Newark, Jameco, etc.). Manufacturers’ information and part numbers are indicated for comparison purposes:

Type/Manufacturer

Number of Pins

Manufacturer’s Part Number

Subminiature D-Shell

Mfg: AMP

www.amp.com

Phone: 800-522-6752

15 (high density)

Plug: 748364-1

Shell Kit: 748677-1

Pins: 748333-2 (strip)

748333-4 (loose)

26 (high density)

Plug: 748365-1

Shell Kit: 748677-2

Pins: 748333-2 (strip)

748333-4 (loose)

44 (High Density)

Plug: 748366-1

Shell Kit: 248677-3

Pins: 748333-2 (strip)

748333-4 (loose)

9 (Standard)

Plug: 205204-4

Shell Kit: 748677-1

Pins: 5-66507-7 (loose)

3-66507-0 (strip)

9 (Standard, Female)

Plug: 205203-3

Shell Kit: 748677-1

Sockets: 745253-6 (loose)

745253-2 (strip)

15 (Standard)

Plug: 205206-2

Shell Kit: 748677-2

Pins: 5-66507-7 (loose)

3-66507-0 (strip)

25 (Standard)

Plug: 207464-1

Shell Kit: 748677-3

Pins: 5-66507-7 (loose)

3-66507-0 (strip)

MiniDIN

Mfg: Shannon Precision, Inc

www.spi-connects.com

Phone: 937-374-2700

8 (MiniDIN)

Plug: MD10-A08P1F

MiniDIN to Serial Adapter Cable

Mfg: Assmann

www.usa-assmann.com

See web site for local distributor

Cable (2.0m):AK-6097

Setup/Operation:

1. How can I use an external DC power supply to power an –AC amplifier?

a. If the external DC power supply has its own shunt regulator, the DC power supply must be connected through the DC Output terminals on the amplifier. If either the internal shunt regulator on the amplifier or no shunt regulator at all are being used, the DC power should be supplied via the AC Input terminals on the amplifier. In this way, fuse protection is provided and polarity of the supply voltage is controlled within the amplifier.

2. How do I set up the amplifier?

a. For general setup instructions see any of the following:

i. Catalog, page G-21, Paragraph 5: Set-Up Instructions

ii. AMC Engineering Notes and Installation Notes.

iii. Advanced Motion Controls CDROM catalog: Engineering Reference -> Installation Notes

3. What mode should I be in?

a. It is up to the system designer to determine what mode the amplifier should be in. Listed below is a brief description of the various amplifier modes. All of the modes listed may not be available on your amplifier.

Open Loop Mode	The input command voltage controls the output duty cycle of the amplifier. This mode is available on brushless amplifiers. Equivalent to voltage mode on brush type amplifiers.
Voltage Mode	The input command voltage controls the amplifier output voltage. This mode is available on brush type amplifiers. Equivalent to open loop mode on brushless amplifiers.
Current Mode (Torque Mode)	The input command voltage controls the output current (torque). The amplifier will adjust duty cycle to maintain the commanded current. This is the suggested mode if an external controller is used which can close the velocity or position loops.
IR Compensation mode	Input command controls motor velocity. IR compensation mode can be used to control motor speed without a velocity feedback device. The amplifier will adjust the duty cycle to compensate for changes in output current. While the command response is linear, accuracy during torque disturbances is not as accurate as a closed loop velocity mode.
Hall Velocity Mode	The input command voltage controls the motor velocity. This mode uses the hall sensor frequency on a brushless motor to close the velocity loop. Due to the low resolution of the hall sensors, this mode is not recommended at low speeds.
Encoder Velocity Mode	The input command voltage controls the motor velocity. This mode uses the frequency of encoder pulses to close the velocity loop. The higher resolution of encoder feedback allows for smooth motion at all speeds.
Tachometer Mode	The input command voltage controls the motor velocity. This mode uses an analog tachometer on the motor to close the velocity loop. Since DC tachometers have infinite resolution, speed control can be extremely accurate with a tachometer; however, they are highly susceptible to electrical noise, most notably at low speeds.
Analog Position Loop Mode (ANP Mode)	The input command voltage controls the position of the motor. This is essentially a modified velocity mode in which an analog device (i.e. potentiometer or transducer) provides position feedback In this mode, the motor speed is proportional to the position error. Amplifier models with the -ANP extension have been modified for quicker response and smaller steady state error in ANP mode.

4. How should I set the on-board potentiometers?

a. The potentiometers are 14 turn, 50kW potentiometers, with one inactive turn at each end and 12 active turns. When the end of potentiometer travel is reached, it will click once for each additional turn.

Pot Number	Purpose	Procedure
1	Loop gain adjustment for open loop, voltage, and velocity modes. CW=increased loop gain. Shipped in CCW position.	Adjust command signal such that the motor is turning at a slow speed (100-200rpm). Slowly turn pot 1 clockwise until the motor begins to vibrate or “hum”. Then turn pot 1 back counter-clockwise until vibration stops, then an additional 1 to 2 turns. Note: If using current mode, it is recommended that you leave pot 1 in the full counter-clockwise position.
2	Current limit. CCW=decreased current limit. Shipped in full CW position.	Determine the peak and continuous current requirements for your system. If available, use on-board switches to set the maximum current limits and ratios. Determine number of turns from full CCW based on this equation: Turns=(I_syst/I_max*12)+1 See How do I set the peak and continuous current limits on the amplifier?
3	Reference in gain. Adjusts the amplifier output to command input gain of the amplifier. CCW=decreased reference gain. Shipped in full CW position.	For velocity or voltage control, turn pot 3 full counter-clockwise. Adjust the command input to 1V. Turn pot 3 clockwise while monitoring motor velocity or amplifier output voltage (depending on amplifier mode.) Turn pot 3 until the required output is achieved for a 1V command (i.e. 1V command = 200rpm motor velocity, or 1V command = 20V amplifier output. This pot may be left in the full clockwise position if a controller is used to close the velocity or position loops.
4	Test/Offset. Provides either an onboard test signal or an offset DC voltage to the command loop. Shipped in the middle of potentiometer travel (7 turns from CCW).	Offset mode (Test/Offset switch to Offset position): Provide a zero volt command signal or pull the REF+ and REF- pins to signal ground. If the motor shaft turns, adjust pot 4 until motion stops. Test mode (Test/Offset switch to Test position): This mode can be used to generate an on-board command signal by turning pot 4 in either direction. See amplifier block diagram for voltage range of test signal.

5. How do I set the peak and continuous current limits on the amplifier?

a. If available, position the Current Scaling switch to the proper position – 100% for full current capabilities of the amplifier, 50% to reduce the maximum current output by half.

b. If available, position the Continuous Current Reduction switch to the proper position – Continuous/Peak current ratio of 50% or 25%.

c. Set the position of Pot 2 (Current Limit) from the full counter-clockwise position based on the following:

Turns = (I_syst/I_max*12)+1

Where: I_syst=Maximum current requirements of the system

Note:

Selection:

Setup/Operation:

Troubleshooting: