Crossbow

OPC servers are for collecting data.  You still need a package to read the data from the OPC server into Visual Studio.  I am not sure what method you intend to use for that.  You may be able to not work with an OPC server and just find communication software for HostLink to VS directly.

Sounds like Indusoft isn't looking at the long word.  Check the data type.

Shouldn't be anything you have to do, it should be on by default.

If you change the IP address of the controller you need to download those changes to the controller.   There is no reason it would return to default if it was set. 

I disagree with Bob on the hub, switches (unmanaged even) are the way to go for traffic considerations. First, did you set a unique IP address on each device?  All of my PLCs come out of the box with the same address set, and that's not going to work when networked.

PWM does not apply to this application.

That product is only sold in India.  Contact the vendor to get the software.

Set an output bit when the button is pressed. Have that bit enable a timer for 0.1 seconds. When the timer finishes, reset the bit.  

The motion control instruction manual, W508, section 2.2.  Complete list of all commands, and there is a column called Single Axis.  the instructions with the circle there can be used with a single axis positioning axis.  You can get it from Omron's website.  You can also access all manuals from the Help menu inside of Sysmac Studio.

You need to provide a whole lot more information.  What robot to start with? In most cases, the answer is NO.  The robot is not a web server.  What you would need to do is collect information on the robot's current position and then create your own way to display that information.

Safety should not have been down when that error occurred.  As you said, I am pretty sure the EIP is only for monitoring and does not affect the safety operation.  This device is too old to offer CIP Safety, only the NX-SL5500 and SL5700 have that.

The motion instruction manual has a table that lists which function blocks can be used on a single-axis positioning axis and which require a motion axis.  That is the only difference... a motion axis can use all commands while the other is effectively a 'lite' axis.

I believe S7-200 also offered a memory card option that plugged into the front... It's possible your program is on the card and it can simply be moved to the new unit. But I don't recall and haven't touched a Siemens PLC since 2005... job change.  Did install several of these back in the day though.  Nice little PLC and great software.

Pretty sure the FX0N-24MR does not have an S/S terminal, while the FX0N-24MR/ES does.

You can't use C252 because it uses the same inputs as your C251.  Review the chart posted above.  It shows if you want a second high speed input you need to use C253 or C255 with inputs X3 and X4. Only X0-X5 are high speed inputs.  You wanted a dual channel input, so there goes 2 inputs, X0, and X1, with X2 allowing a reset input.  Another dual channel input, there goes 2 more, X3 and X4, with X5 allowing a reset input.  That's all 6 high speed inputs used.

That's a hell of a markup, those PLCs were under $1000 even for the largest model.  If you can get MicroWin and the cable and get online, you may still be able to back up the existing program and source a similar PLC from someplace like Radwell. Keep in mind S7-200 is obsolete and was replaced by S7-1200, so support for it will be limited in the near future.

There is a list in the manual for the device that shows which inputs can be used in which modes with high speed counters.  I think you can get 2 AB phase, to get to 6 you would need single phase encoders.  But it's very specific which inputs are used and which counter numbers they are attached to.  The manual should be in the downloads section here, I forget the number.

Pretty sure without the ES they are fixed (I forget sinking or sourcing) but it is different than the ES models that are selectable.

Omron only publishes the PFH numbers.  They are in the manuals.

SIL and PL ratings are for safety PLCs, not applicable to standard PLCs like NX1P2. Category and PL are defined by ISO 13849-1. SIL is defined by IEC 61508. The NX-SL safety controllers are rated SIL3, PLe

Check the manual on the card settings, there is a pulse rate measurement function built right into that card.  In the settings you can set the Time Window in milliseconds.  The manual should explain how this is set and how to program it.

What brands have you used?  I have never seen an analog card that put out actual value.  Everything I have worked with puts out an integer numeric value indicating the range, like 0-1000, 0-4000, 0-8000, 0-32000, etc.

You need to provide more info.  Which PLC?  Does it have a real time clock?  You should be able to use simple comparisons to determine the time of day and prevent and output from turning on outside that window, actually pretty easily.

A VFD does not get set up as a motion axis, so you don't need a full motion controller.  Only servos and steppers are motion output axes.  You would not be able to use any of the motion control function blocks to control a VFD, at least not that I am aware of.  What exactly are you trying to do?  Control speed and verify position with an encoder?  How is the VFD being controlled?  You should be able to do some calculations with the encoder speed to determine how fast and how far the motor is moving.

Are the PLC and HMI in the same project?  if so, it should be automatic.  I've done the same thing in the past and had no issues.  Building the HMI project should show a list of errors. Deleting and recreating the variable on the PLC side is likely not the issue, have you tried the same on the HMI side?  Have you looked at Variable Mapping in the HMI project and verified the PLC name and data type are correct?