02-17-2012 01:03 AM
hi anyone help me please !!!i'm beginning labview
I use labview 2009 sp1 , MAX 4.6 ,PCI 7354 ,umi 7774 motion interface. i want to drive DC servomotor and p
osition control with encoder.
i have questions?
UMI 7774 have to connect with encoder that have A,A-,B,B-,index,index- ?
If not how to do?
Do i have to wire inverting gate?
I want to test the encoder test on MAX and wiring follow manual but no have encoder signal.
If measuring with oscilloscope have a signal. why is it?
thank for any advice you have
P.S. sorry my writing is bad. If i am not polite so sorry.
Solved! Go to Solution.
02-17-2012 07:49 AM
What kind of encoder are you using?
Most incremental encoders have three channel output, and also in many cases the outputs are diffential lines/pairs.
However, the encoder inputs of the UMI box accept BOTH differential encoder output and TTL encoder output without changes.
Check the specifications of your encoder. If possible, post a link to the encoder manufacturer website with encoder specifications.
02-19-2012 09:15 PM
i use second hand motor " pittman 14202 series".
a name plate is 14202D335-R1 385-22-001 24VDC 1000CPR 05-10-00.
a encoder maybe E30A. It have not Index channel because i measure A signal and Index signal.they're inphase.It's strange.
Do you think about it?
and if i haven't Index channel. what should i do it?
thank you very much for reply
02-20-2012 08:27 AM
BTW it is possible to generate a differential signal (A /A etc) from a single-ended TTL signal, but usually you do not use an inverter to generate the /A signal. There are ICs like the AM26LS31 which can generate proper differential signals with proper signal levels and impedances.
However, with the UMI box, this is not needed. The encoder inputs will accept both single-ended TTL signal as well as differential signals without modification.
02-20-2012 08:33 AM
According to your datasheet, the E30A encoder has A, B and index channel. All channels have single-ended TTL level output so it should be no problem to connect it to the UMI box, just connect it to the encoder A, B and index inputs and do not forget a GND connection to the digital GND terminal of the UMI box. Also, of course you need a supply voltage for the encoder.
The index signal should occur only once per revolution.
02-20-2012 11:17 AM
as you tell "The index signal should occur only once per revolution" so maybe no have Index input because the signal from index input inphase with the A signal.it isn't correct.
thank you for reply