Forces

[FauxEng 0]

I am having difficulties with my first time in a DL06 PLC. How do I Force bits or values while online? I'm connected to the PLC, have the data view open with the edit column visible, have hit the toggle button (or entered a value for a V address), clicked the "write edits to the PLC" button...... and nothing. No changes were made. I've tried X, Y, and V values. What am I missing?

[milldrone 0]

FauxEng, Are any of the values you tried to change written to in the program? Are you trying to change the value of an input that exists in hardware? Here is a quote from the manual " Service Peripherals and Force I/O After the CPU reads the inputs from the input modules, it reads any attached peripheral devices. This is primarily a communications service for any attached devices. For example, it would read a programming device to see if any input, output, or other memory type status needs to be modified. There are two basic types of forcing available with the DL06 CPUs: • Forcing from a peripheral – not a permanent force, good only for one scan • Bit Override – holds the I/O point (or other bit) in the current state. Valid bits are X, Y, C, T, CT, and S. (These memory types are discussed in more detail later in this chapter). Regular Forcing — This type of forcing can temporarily change the status of a discrete bit. For example, you may want to force an input on, even though it is really off. This allows you to change the point status that was stored in the image register. This value will be valid until the image register location is written to during the next scan. This is primarily useful during testing situations when you need to force a bit on to trigger another event. Bit Override — Bit override can be enabled on a point-by-point basis by using AUX 59 from the Handheld Programmer or, by a menu option from within DirectSOFT32™. Bit override basically disables any changes to the discrete point by the CPU. For example, if you enable bit override for X1, and X1 is off at the time, then the CPU will not change the state of X1. This means that even if X1 comes on, the CPU will not acknowledge the change. So, if you used X1 in the program, it would always be evaluated as "off " in this case. Of course, if X1 was on when the bit override was enabled, then X1 would always be evaluated as "on". What this means is the "force" form the data view will last for one scan only if it is being written to. If you want to permanently force something you need to go to "PLC", "setup", "overrides" click on "add" type in the address you want to override, then select it, then click on force on or off. Oh!!!!!!! and the ever popular is the PLC in run? Vaughn

[FauxEng 0]

The manual wasn't specific in how to enable the forces. I wasn't looking for "overrides" in a menu, but see it now. The next time I'm online with the PLC, I'll try it. Thank you!

[Hipoguy 0]

Faux Engineer, If you use Data view in DS5 and click the E in the upper left hand corner you will be able to write your elements in the columns provided. using the small icon of the plc with the arrow above it and the one with multiple arrows above it . one is for single and one is for multi edits. Also be careful some of your forces may have no effect if you are over writing them somwhere else in your code. regardless of what you change the location too it will be filled in with your prdefined value when the PLC does its next scan.