Connecting Amp Enable

[keithorr]

I am connecting servo amplifiers to an ICM2900 OPTO module. I am configuring for low enable (replacing the ic chip with a 7406 model), pulling the resistor pack to make the it an open collector (ampenx,y,x....) .

The enable pin on the servo amplifier sources 15v. (Sanyo 27BA100FFT and 27BA030FXT amplifiers)

The goal is to sink the signal to ground.

I read and have been informed that the current limit of the ic chip is 40mA.

When I manually short the amplifier enable pin to ground through a mulit-meter, the readings are 7.4-7.6mA at about 12.75vdc.

I have seven amplifiers.

How do I protect the ic chip? I assume I will place resistors in line, but don't know how to determine the proper size or if that is the right strategy.

I think this smiliey describes it best

Thanks

[agentsmith]

To get started on the right foot it may be best to contact Galil directly on this issue. This is a special case. Most people don't have to do this. I myself never had to use resister pack or build build special circuits. But it is possible to do this. If you contact Galil they can help you and make sure that your circuit will not damage the board. I've been using Camsoft for years and this sounds like a deep subject that is best explained by someone that really knows what their doing.

Good Luck

[keithorr]

Mr. Smith
I thought I would try here just to see. Actually the solution occured to me on the way home last night. I am connecting only 4 amplifiers per ICM module, not 7 (4 on one module, 3 on the other). I was fixating on a 25¢ part and forgetting the context. Four amp enable lines drawing 7.6mA is within the limits of the chip.
In the words of Emily Litella, "Nevermind".

[murphy625]

I had a problem like this also.
My servo uses a 24volt enable signal and the icm only accepts 5 votls.

I used the 5 volts to drive a stand alone Opto22 relay. (cheap $$)
The enable from the ICM turns the opto on and off and the opto passes the 24 volts from the enable circuit.

Works great. No problems.

Murphy

[intrusion]

Murphy,

That sounds good, however there is a way to get 24V on the ICM for the enable circuit. I read in the Galil manual and CamSoft's that you can remove a resister pack (RP1) and apply your own resister in series with the external power supply up to 24V.

intrusion

[murphy625]

Originally Posted by intrusion Murphy, That sounds good, however there is a way to get 24V on the ICM for the enable circuit. I read in the Galil manual and CamSoft's that you can remove a resister pack (RP1) and apply your own resister in series with the external power supply up to 24V. intrusion

I just found it much easier to use an opto relay.. The new G4's have a manual switch on them that lets you turn them on and off manually without the computer. (comes in handy sometimes).

I would also think that it would provide another level of protection to the computer due to the fact the relays are optically isolated.

Just a suggestion.. I'm just a newbie.

Murphy