Wiring up the Alarm output on Leadshine AM882

[EddyCurrent]

There are drawings here; http://www.mycncuk.com/threads/6565-...2213#post52213
of how I wired them.

[m_c]

Turned out really simple. In the software set the alarm to go "LOW". Run the E-Stop though as many switches as you need then end at the "ALM +" of the first drive then "ALM -" to the "ALM +" of the next and so on. After the last drive "ALM -" goes back to the control board "GND" and that's it. Job done. If any drive goes into alarm, the circuit is broken and E-Stop is activated.

Happy Days

One thing to be aware of with doing this, is the alarm outputs may have a slight voltage drop (I've just checked the EM manual and it doesn't give any specs, but electronic open collector type outputs typically have a voltage drop, unlike true mechanical relay contacts). So if you connect multiple drives in series, you risk increased interference/noise issues.
I.e. if you're connecting to a TTL level type input, which needs a guaranteed voltage below 0.7V to be active, if you connect 4 drives with a 0.1V drop, you then only have a noise margin of 0.3V.

Off course, the exact effect will vary depending on the kind of input you're using. If you were to get noise problems, the simplest solution would be to add a relay controlled by the alarm/e-stop circuit, as a reasonable amount of current is needed to activate the relay, which should be far greater than anything noise/interference would cause.

[joel0407]

One thing to be aware of with doing this, is the alarm outputs may have a slight voltage drop (I've just checked the EM manual and it doesn't give any specs, but electronic open collector type outputs typically have a voltage drop, unlike true mechanical relay contacts). So if you connect multiple drives in series, you risk increased interference/noise issues.
I.e. if you're connecting to a TTL level type input, which needs a guaranteed voltage below 0.7V to be active, if you connect 4 drives with a 0.1V drop, you then only have a noise margin of 0.3V.

Off course, the exact effect will vary depending on the kind of input you're using. If you were to get noise problems, the simplest solution would be to add a relay controlled by the alarm/e-stop circuit, as a reasonable amount of current is needed to activate the relay, which should be far greater than anything noise/interference would cause.

Thanks mate. Makes sense. I don't know much about open collectors.

Happy Days