![]() touching numeric or string entry button brings keypad as expected but the initial focus is not on touched button/entry - manual says that up to 4 keypad screens are usable so i created three (one for ASCII and two for numeric, one left and one right). for example: - loading of ASCII keyboard is still slower than desirable (shows up button by button) but i don't think that this can be changed and it's not much of a problem (it's around a second which is not too bad). there are few other small things that could be better. no contest between 115.2kbps and 9600bps i didn't see NTLink 1:1 on PLC side, so I used 1:N and the "NT/PC Link Max" remained at zero but it worked for me. cable PT to PLC remained the same and everything worked like a charm. Thanks everyone (specially gtsupport) i forgot the darn "memory switches" so had to dig through all menus under MAINTENANCE to find it (very obscure) but once i got there it was matter of changing port settings and rebooting machine. the point is that pulse length should not have "confusing effect" on stepper drive unless they is outside drive's specs (too short). there are other devices like hobby servo motors that do respond to pulse length but that is another story. drive is supposed to count pulses (or transitions) - regardless of the pulse length. i have no problem with adding load resistors if system seam to be sluggish (so far I never used them or felt need for them) but i don't quite like statement "stepper driver may interpret the input step signals as extra steps". if you expect fast performance, you should consider alternatives like servos, stepper are always going to be slow. if R3 is connected as you describe it, it is not part of voltage dividing circuit, it is load resistor. ![]() applied motion has support line that will answer all your questions. i wouldn't spend much time with another manufacturer literature. R2 is just voltage dropping/ current limiting resistor. ![]() you could drop in picture of the circuit (i'm not exactly ready for much thinking on friday evening). last unit i used was STP-DRV-4035 from Automation Direct (which has very clear user manual: STP-SYS-M) to answer your questions: 0. inserting resistors for voltage drop to drop voltage is common practice when using higher voltage outputs. good drives have isolated inputs and allow you to wire them either as sink or source. I've used steppers only few times but it seams that most of them expect 5V inputs. outputs P0 and P1 are also available as line driver outputs (P0+, P0-, P1+, P1-). if the outputs P0, P1, DIS and CLR are 24V rated, it would make sense to keep T1 separate so enduser can choose voltage (+5V or +24V for example). Terminal T1 can be connected to positive terminal (use 3.3k resistors as load). the ouput circuit of the EM253 shows sink outputs with 3.3k pullup resistors. converting low voltage input to high voltage input simply means adding external series resistor and this is R2 in yur case. inputs that are supposed to operate at higher voltages have higher resistor value (2.6k). if such inputs are designed for 5V, they use low value internal resistor such as 220.680 Ohm. optocouplers need some current to operate (turn on) and this value is usually in 2.20mA range for digital optocouplers. if the input is some high impedance circuit (like OpAmp for example) then you would have to use external voltage divider many devices do have isolated inputs (just like EM253 for example) where phisical input (such as STOP for example) has simply an optocoupler and series resistor (in this case 5.6k). These images confirm what was mentioned before: - R2 is voltage drop / current limiting resistor - R3 is load resistor choosing interface circuitry depends on characteristics of input and output that are to be connected.
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