ElmoMC CANopen DS 301 Implementation Guide - Manual (Page 111)

Object 0x2F60 – Zero torque threshold
In the DS402 profile torque, it is necessary to define a window around the target torque
‘0’, to obtain a good indication of when the target is reached. By default, this window is
5% of the Current Limit (CL [1]). It is possible to modify the percentage by means of this
object.
Defines the '0' torque (current) for profile torque 'target reached' indication.
In DS402 Profile Torque mode, when the torque command is set to '0', it is possible that
the current feedback may vibrate, thus preventing a steady state. For this case, object
0x2F60 defines a threshold for the '0' value:
ƒ
The value is defined as a percentage of the Continuance Current Limit (CL[1]).
ƒ The object units are 'internal unit' form.
ƒ The WS[56] command retrieves the "ampere to internal units" factor.
To calculate the Continuance Current Limit (CL[1]):
Threshold Current [Internal Units] = CL [1] [Internal Units] / Object 0x2F60
CL [1] [Internal Units] = CL [1] [Amperes] * WS [56] [Internals Unit/Amperes]
Example:
If the required window of 2.5 % of our CL [1] and CL [1] is 3 Amps, then according to the
previous formulas:
CL [1] [Internal Units] = 3 Amp * 1358 int units of current/Amp
CL [1] [Internal Units] = 4074 int units of current.
CL [1] [Internal Units][2.5%] = CL [1] [Internal Units] * 0.025
CL [1] [Internal Units][2.5%] = 4074 * 0.025 [Internal Units] = 102 [Internal Units]
This value is the window that we want to apply:
Object 0x2F60 = CL [1] [Internal Units]/Window Current [Internal Units]
Object 0x2F60 = 4074 / 102 = 40
• Manufacturer-specific options
• Object description:
Index 2F60h
Name Zero torque threshold
Object code VAR
Data type UNSIGNED16
Category Optional
CANopen DS 301 Implementation Guide Manufacturer-specific Objects
MAN-CAN301IG (Ver. 2.1)
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