Yaskawa Motors – Mitchell Electronics Inc

This is the TI-3000JX option for Yaskawa 8 pole motors using incremental UVW, C channel and 12 and 15 bit absolute encoders.

Note: This option does not support the 13, 16 and 17 bit serial absolute encoders on the Sigma II motors.

The Yaskawa support was developed before the Generic Encoder support. The Yaskawa encoders supported by the TI-3000JX can now all be run under the Generic Encoder selection. Using the Generic Encoder selection requires entering more information before the run (as with all Generic selections). Some C Channel type encoders with magnetic disks must be run with the Generic Encoder selection because the commutation signals and the index pulse do not have the same angular relationship as with the other encoders.

General Comments

There are 3 major types of Yaskawa quadrature type incremental encoders (A, B, and Z lines), and there are serial encoders used on the newer Sigma II motors. The quadrature type encoders are supported by the TI-3000JX, but support for the serial encoders is not yet available.

Types Supported

The following list shows the Yaskawa encoders that are currently supported by the TI-3000JX option. The 3 major types of Yaskawa encoders currently supported are fundamentally quadrature type, but they have some differences from the typical and require some special treatment. Part numbers often are not clearly marked on the encoder boards, so identification is not always easy. Often there will be an encoder part number on the encoder cover. This section will include part numbers associated with the encoders and motors, and signal lines shown in the cable documentation can be used as an aid in identifying the encoders.

Yaskawa encoders are used on Allen Bradley 8500 Series Digital Servo Motors. See the following section on absolute encoders when working with Allen Bradley motors.

Quadrature Incremental with 3 Commutation Channels

One Yaskawa incremental style includes 3 commutation true lines and 3 commutation complement lines (U, U*, V, V*, W, W*). A typical part number for this type of encoder would be UTOPI-600VA. As per the chart in the identification section, these are 24,000 counts per revolution. This is the simplest, most straight-forward type of Yaskawa encoder.

Motors with the U V W encoders should be run under the Yaskawa U V W selection.

Once you have connected the motor to the TI-3000JX and verified operation in DEBUG mode, you can run the motor with the RUN button. The motor will start running using the commutation signals. During the first two rotations, it will measure the number of counts/revolution and index the encoder count. From that point forward, it will run using the encoder count for commutation.

Quadrature Incremental with Single C Commutation Channel

The second Yaskawa incremental encoder type multiplexes the 3 commutation signals onto one pair of lines -C and C*. Some typical part numbers for this type encoder are, UTOPH-81AWF, UTOPH-40AWM, UTOPH-81AUS, and UTOPI-81AUS. Part numbers for this type of encoder will start with UTOP whereas part numbers starting with UTOMA would be absolute encoders.

The single pair of C channel lines represents Z, U, V, or W. Please refer to the TI-5000JX manual for a more complete explanation of the C Channel encoders. The TI-5103 Yaskawa Adapter Module can convert the C channel information to U, V, W, and Z signals so you can run this encoder as a standard incremental encoder with U V W lines.

C Channel with TI-5103 Adapter Module –

C Channel encoders with the TI-5103 Yaskawa Adapter Module can be run using the UVW selection as describe above.

C Channel with TI-5103 Adapter Module –

Some of these encoders utilize a 17 pin circular connectors and bring out an index pulse on the K and L lines. In such cases where the index pulse is provided, the encoder can be run without the TI-5103.

If you are not using the TI-5103 module, you must use the Yaskawa C Chan selection.

When you use this selection, you must always go into DEBUG mode and rotate the motor shaft a couple turns to index the encoder and measure the number of encoder counts/revolution. Then the RUN key may be pressed to run the motor.

C Channel with Magnetic Disk –

You may encounter some C Channel encoders made by Sony Magnescale, and these must be run using the Generic Encoder selection. For other Yaskawa encoders, there is a definite relationship between the commutation pulses and the index (Z) pulse. The position where the index pulse occurs will be very close to one of the positions where the U commutation pulse changes state, the V commutation pulse is LO and the W commutation pulse is HI. For a correctly aligned encoder, this would occur near the –U +V +W lockup position. This relationship between the index pulse and the commutation signals apparently does not exist for the Sony Magnescale encoders. In fact, in several different motors of this type that we have investigated, no consistent relationship was found. The positioning of the index pulse relative to the commutation pulses appeared to be random. Normally, you can use the index pulse to align Yaskawa motors, but we believe that using the commutation pulses is the correct method for motors using the Magnescale encoders. Motors using these encoders tend to be very small physically. A representative part number is SGM-A5A3TF11X.

Absolute Encoders

The third type of supported Yaskawa encoder is commonly referred to as an absolute encoder. Some of
these encoders are used on Allen Bradley 8500 Digital Servo Motors. Typical part numbers for absolute encoders are UTMAH-B15ASB, UTMAH-B15BSB and UTMAH-B15A5B1. The part number always starts with UTMA instead of UTOP, so they are more easily identified than the first two types discussed. The absolute encoders are available in several different numbers of counts/revolution. The 4,096 (12 bit) and 32,768 (15 bit), 65,536 are supported. The motor model SGM-04VW14B is an example of a 4,096 count/rev encoder. The 13, 16 and 17 bit ABS encoders are serial encoders and are not currently supported by the TI-3000JX. For additional information on the Yaskawa absolute encoders, please see the TI-5000JX manual.

Motors with the ABS encoders should be run under the Yaskawa ABS selection.

Absolute Encoder Rest Procedures

You may encounter an absolute encoder that is not producing any quadrature pulses and not showing any commutation states when you check it out in DEBUG mode. Assuming it is a good encoder, this probably means the encoder is in need of a reset. The reset is usually required when an ABS encoder has not been connected to a battery for a period of time. When this occurs, absolute encoders can get into a condition in which they will not produce quadrature pulses until a reset procedure is performed. The reset procedure is different for a 12 bit versus a 15 bit ABS encoder. The procedure for the 15 bit encoder usually goes smoothly. The 12 bit encoders seem to be harder to reset for some reason.

15 BIT:

On the sample 15 bit encoders we have used, there are two LED indicators on the top and bottom of the 2nd encoder printed circuit board. The top LED (1LED) seems to come on and go off during power up when the encoder is working normally. The bottom LED (2LED) seems to flash twice while the 1LED is ON. This probably corresponds with the 2 bursts of data coming from the encoder to update the drive and computer. When the encoder is in need of a reset, 1LED will turn ON when the power comes on, but it will not turn right back OFF like normal. Also in this condition, no quadrature pulses will be generated as the encoder is rotated. In this case, the encoder must be given a RESET and be supplied with a battery backup. The reset procedure is as follows:

Disconnect all power from the encoder. Connect a shorting jumper from pin R to pin S, and leave it connected for a minimum of 4 minutes.
Disconnect the jumper from pin R to pin S after 4 minutes, and connect a battery (or 5 V supply) with + to pin T and ground to pin S.
Proceed to power up the encoder in the normal manner.

When the encoder powers up, the LED indicators should behave in the normal manner, and the encoder should produce quadrature pulses when it is rotated. On the first power-up after RESET, it seems to be very important that a voltage be connected to the battery pins before voltage is applied to the normal 5 volt pin. The encoder seems to have some built-in logic that will not allow it to work without this voltage. However, it appears to be required only on the first power-up, and subsequent power-ups apparently work fine without the battery voltage as long as the internal capacitors have not lost their charge. This procedure should cause the encoder to produce quadrature pulses and allow you to perform all the normal tests with the TI-5000JX tester. The TI-5017 Cable is designed for the 15 Bit ABS encoder and brings out the lines required to perform this procedure.

12 BIT:

There is a second reset procedure which is required for 12 Bit Absolute encoders. The pin configuration is identical to the 15 Bit Absolute except for the addition of S and S* lines on pins K and L respectively. This encoder is also supported by the TI-5017 Cable. These encoders can be tested as 4096 count/rev quadrature pulse encoders. Like the 15 bit, they may require a reset before they produce pulses for testing. The procedure that seems to work is similar to but a little more complex than the 15 Bit Absolute. The procedure that has worked for us is as follows:

With the encoder powered down, connect a battery (or 5 V supply) with + to pin T and ground to pin S.
Connect a shorting jumper from pin R to pin S, and leave it connected for a minimum of 4 minutes.
Disconnect the jumper from R to S and connect a shorting jumper from pin R to pin T (that is to the
battery or 5 V supply) for 4 or 5 minutes.
With the jumper still connected from pin R to pin T, power up the encoder in the normal manner.
Disconnect the jumper from pin R to pin T. Cycle the power, and the encoder should power up with the LED flashing green then off. The encoder should produce A, B, and Z pulses. If the Red LED does not go off, try cycling the power again.

Notes:

Make sure that you leave the battery voltage connected after the reset. If you remove that battery voltage, you will have to repeat the reset procedure.
It seems to be common for this procedure not to work the first time. You may have to repeat the procedure. I think you can probably repeat steps 3 – 5 rather than going all the way back to step 1. Going back to step 1 is fine, but it does take longer.
The R, S and T pins refer to the 17 pin circular connector. If you have a 12 or 15 pin rectangular AMP connector (other something else), you will need to use the same functional lines. The following table should help with that:

These are the colors that seem to be used most of the time by Yaskawa.

Identification

Some further description of the part numbers may be helpful. The following description will not cover all encoders, but hopefully it will help identify many of them. We can work from an example – the UTOPH -600UBXXX. The UT indicates a special detector which is an encoder for AC servo motors or AC spindle motors. The OP designation indicates incremental encoder (optical encoder) types as opposed to the MA designation for the absolute encoder (multi-turn). The H means coupled with a plate spring for the motor, whereas E means coupled with couplings for the motor and I means built-in. The 600 indicates the number of pulses per revolution. The number of pulses per revolution and the corresponding number of counts per revolution (which is 4 times the pulses per revolution) is indicated in the following chart:

Incremental Encoders

Absolute Encoders

The UB is the name of the encoder series. The last 3 numbers (indicated by XXX in the example) have to do with the cable length, connector type, customer spec., version, etc.).

The 16 and 17 bit absolute encoders are serial encoders, and are not supported by the TI-3000JX at this time.

Feedback Type Selection

Pressing the FBK TYPE key will provide the following selections for Yaskawa:

P8 U V W – 8 pole motors using a U V W incremental encoder or C Channel encoder with
the TI-5103 Yaskawa Adapter Module.
P8 ABS – 8 pole motors using a 12 or 15 bit absolute encoder.
P8 C Chan – 8 pole motors using a C Channel encoder without the TI-5103 Yaskawa
Adapter Module.

Select the appropriate type and connect the encoder cable for the type selected.

Debugging

After the type selection and cable connections have been made, a simple debugging sequence can verify that the motor is ready to run. Performing this debugging check can save a great deal of time and provide confidence in the setup. Skipping this debugging check can cost a great deal of time, and could cause damage to the amplifier or possibly even the motor.

The debugging sequence is as follows:

Press the DEBUG key to put the TI-3000JX in DEBUG mode.
Rotate the motor in the forward direction (CCW looking at the shaft for Yaskawa) and verify that the UVW pulses on the display are correctly moving through the commutation pattern as follows: HLL, HHL, LHL, LHH, LLH, and HLH. It is essential that these six commutation steps are generated on the TI-3000JX. Note: The encoder may need to turn a couple turns to index before the commutation
data will be displayed.
Connect a bench power supply to the armature leads (amplifier not connected) with the polarity +U and –V. Verify that, at each rotor lockup position, this produces a commutation pattern of V =H, W=L and U at the position where it will toggle between H and L with a very small motion of the motor shaft.
Move the minus lead of the power supply from the V to the W lead. Verify that, at each rotor lockup position, this produces a commutation pattern of U=L, V =H, W at the position where it will toggle between H and L with a very small motion of the motor shaft.

Passing the above debugging checks is a necessary condition for running the motor. If any of these checks failed, there is absolutely no point in trying to run the motor, and you risk damaging the amplifier or possibly the motor by doing so.

If it does not pass the Debug check, review your setup and correct any mistakes. Only attempt to run the motor after it passes the Debug check.

After the initial successful debugging, it is no longer necessary to go to debug mode before each run. However, it does provide a chance to check that the brake is released (if it has one) and that the motor is indeed ready to run.

Running

After a successful Debug check, perform the following sequence to run the motor.

Connect the motor armature leads to the amplifier using the appropriate connectors.
Press the RUN key to enable the amplifier. The following check list will appear on the display.
a. Are hands and clothing clear of moving parts?
b. Is the motor mounted securely?
c. Is the speed pot set to the zero (stopped) position?
Press the RUN key again after insuring that the check list is satisfied.
The RED LED on the amplifier should change to GRN. If it does not, make sure that the cable from the TI-3000JX to the amplifier is connected correctly and that power has been applied to the amplifier.
Turn the potentiometer either direction from the zero setting, and the motor should begin turning. The bottom line of the display should show the RPM reading.
Returning the pot to zero and moving it the other direction from zero should reverse the direction of the motor.