User manual

Brick Controller User Manual
PinOuts and Software Setup 23
Functionality, Safety Measures
There are a couple of safety and functionality measures to take into account when an external encoder
power supply is utilized:
 Power sequence: encoders versus controller/drive
It is highly recommended to power up the encoders before applying power to the Brick Controller
 Encoder Power Loss (i.e. power supply failure, loose wire/connector)
The Brick Controller, with certain feedback devices, can be setup to read absolute position or perform
phasing on power-up (either automatic firmware functions, or user PLCs). If the encoder power is not
available, these functions will not be performed properly. Moreover, trying to close the loop on a motor
without encoder feedback can be dangerous.
Caution
Make sure that the encoders are powered-up before executing any
motor/motion commands.
Losing encoder power can lead to dangerous runaway conditions, setting the fatal following error limit
and I2T protection in PMAC is highly advised.
Caution
Make sure that the fatal following error limit and I2T protection are
configured properly in PMAC.
With Commutated motors (i.e. DC brushless), a loss of encoder generally breaks the commutation cycle
causing a fatal following error or I2T fault either in PMAC or Amplifier side. However, with non-
commutated motors (i.e. DC brush), losing encoder signal can more likely cause dangerous runway
conditions.
Note
Setting up encoder loss detection for quadrature encoders is highly
recommended. Serial Encoders normally provide a flag or timeout
error bit that can be used for that function.