AR absolute battery install with RS-485 (ModBUS RTU)

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AR absolute battery install with RS-485 (ModBUS RTU)

Post by om_tech_support_MD » Tue Apr 02, 2019 1:36 pm

To make the AR series absolute, you need to connect the battery to store the position. As an absolute system it will store the electrical home position even after power is removed. With an absolute system, you may not need a home or limit sensor. Without the battery, when you turn on the driver, your current position becomes your new electrical home position. In the case without a battery, you need to add a home sensor to find the home position in the event of power removal.

Just a few notes on connecting the battery to make installation easier. The battery needs 32 hours to fully charge (step 2 of 6). The battery can store the position for approximately 15 days when fully charged.

Reference 1, page 48
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Reference 2 is steps 1-6 on how to set the absolute system with the battery.

Reference 2, page 166
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First complete step 1 by turning off all the power to the driver and connecting the battery. The battery is connected to the CN10 port on the bottom of the driver. This is covered in reference 3 and 4.

Reference 3, page 24
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Reference 4, page 38
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Then, complete step 2 by turning the power back on. Make sure to wait 32 hours for the battery to fully charge before moving on to step 3.

This is a quick intro startup guide on Comtest PRO, the test software that was used in this walk through. ... php?id=628

This is an example of how to write a query in hex. The slave address on AZ can be set from 1-31. Function code 06h is to write to a holding register. Function code 03 is to read from a holding register.
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Step 3. Write to address 965 (03C5 hex). The factory setting “disable” is 0. Write 1 to “enable”. Use reference 5.
Example: [01h] [06h] [03h] [C5h] [00h] [01h] [58h] [73h]

Reference 5, page 238
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Then you need to write to the non-volatile memory. Register Address 403 (0193 hex). Be sure to write to 0 first then write to 1. Use reference 6 and the example below.
Example: [01h] [06h] [00h] [C1h] [00h] [00h] [D8h] [36h]

Then: [01h] [06h] [00h] [C1h] [00h] [01h] [19h] [F6h]

Reference 6, page 230
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First write to setting range 0. Then write to setting range 1 second
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Step 4, Power cycle the driver for one minute.

Step 5. Reset the absolute position error alarm. Write to register address 387 (0183 hex). Use reference 6.

Example: [01h] [06h] [00h] [B7h] [00h] [01h] [F8h] [2Ch]
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Step 6.
Do not power cycle the driver until after you use the position preset, P-PRESET, or you will have to start all over. After hitting the absolute position error Reset, jog/move to the location you want to make your home position. The write to register address 395 (018B hex). Use reference 6.

Now you can power cycle the driver and your electrical home position will be stored after power is removed.

For some final notes on properly handling the battery, please reference 7, page 16 ... df#page=16

Should you have any further questions please contact us at [email protected] or call at 1-800-GO VEXTA.

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