Re: Hp 1025
Arnau Cyr
Table of Contents Title 46.2. Motor Vehicles Subtitle III. Operation Chapter 10. Motor Vehicle and Equipment Safety Article 3. Lights and Turn Signals 46.2-1025. Flashing amber, purple, or green warning lights
2. Vehicles used in constructing, maintaining, and repairing highways or utilities on or along public highways, or in assisting with the management of roadside and traffic incidents, or performing traffic management services along public highways;
3. Vehicles used for the principal purpose of removing hazardous or polluting substances from state waters and drainage areas on or along public highways, or state vehicles used to perform other state-required environmental activities, provided that the amber lights are not lit while the vehicle is in motion;
8. Fire apparatus and emergency medical services vehicles, provided the amber lights are used in addition to lights permitted under 46.2-1023 and are so mounted or installed as to be visible from behind the vehicle;
11. Vehicles used to collect and deliver packages weighing less than 150 pounds by a national package delivery company that delivers such packages in all 50 states, provided that the amber lights are lit only when the vehicle is stopped and its operator is engaged in such collection and delivery;
12. Vehicles used to transport petroleum or propane products, provided the amber light is mounted on the rear of the vehicle and is lit when parked while making a delivery of petroleum or propane products, or when the vehicle's back-up lights are lit and its device producing an audible signal when the vehicle is operated in reverse gear, as provided for in 46.2-1175.1, is in operation;
14. Government-owned law-enforcement vehicles, provided the lights are used for the purpose of giving directional warning to vehicular traffic to move one direction or another and are not lit while the vehicle is in motion;
20. Vehicles used by municipal safety officers in the performance of their official duties. For the purpose of this subdivision, "municipal safety officers" means municipal employees responsible for managing municipal safety programs and ensuring municipal compliance with safety and environmental regulatory mandates;
21. Vehicles used as pace cars, security vehicles, or firefighting vehicles by any speedway or motor vehicle race track, provided that the amber lights are not lit while the vehicle is being operated on a public highway;
22. Vehicles used in patrol work by members of neighborhood watch groups approved by the chief law-enforcement officer of the locality in their assigned neighborhood watch program area, provided that the vehicles are clearly identified as neighborhood watch vehicles, and the amber lights are not lit while the vehicle is in motion;
23. Vehicles that are not tow trucks as defined in 46.2-100, but are owned or controlled by a towing and recovery business, provided that the amber lights are lit only when the vehicle is being used at a towing and recovery site;
24. Vehicles used or operated by federally licensed amateur radio operators (i) while participating in emergency communications or drills on behalf of federal, state, or local authorities or (ii) while providing communications services to localities for public service events authorized by the Department of Transportation where the event is being conducted;
26. Vehicles used for hauling trees, logs, or any other forest products when hauling such products, provided that the amber lights are mounted or installed so as to be visible from behind the vehicle.
C. Vehicles used to lead or provide escorts for funeral processions may use either amber warning lights or purple warning lights, but amber warning lights and purple warning lights shall not simultaneously be used on the same vehicle. The Superintendent of State Police shall develop standards and specifications for purple lights authorized in this subsection.
D. Vehicles used by police, firefighting, or emergency medical services personnel as command centers at the scene of incidents may be equipped with and use green warning lights of a type approved by the Superintendent. Such lights shall not be activated while the vehicle is operating upon the highway.
By default, it was assigned to the Digital Input $IN[1025]. But I saw multiple assignments by default to $IN[1025], and being new to this, I assumed they had to be assigned to different inputs. So, I assigned $MOVE_ENABLE to $IN[100]. However, this doesn't seem to have resolved the issue. And the assignment change hasn't been taken by the controller. It is still defaulted to $IN[1025].
Should $MOVE_ENABLE be assigned to an input other than $IN[1025]? The error I get is quite clear about this. But is there some weird resetting that happens when I go back and forth between T1 and AUT EXT?
but in EXT mode robot i controlled by PLC. this signal simply give a way for PLC to say "oooops this did not go according to plan, better stop everything....". so if PLC needs, it can stop robot easily and quickly. that may not sound like something special but let me tell you - it is a very important feature.
some 15-20 years ago i was asked to assist with programming of the machine which used linear actuator as an adjustable hard-stop for another device. don't remember brand but basically it was just a linear jack that was controlled over profibus. it would move to programmed position and stay there for a while. the actuator was not very fast (maybe 80mm/sec) but it was very strong and stroke was less than 500mm. unfortunately there was nothing tied into it to stop it directly. so in case one needed it to stop, all one could do is issue sequence of commands. each command was telegram of few bytes containing command word and bunch of other parameters. it was not on a safety circuit because it was inaccessible by operator. but it could do significant damage that would be mess to repair.
unfortunately it did not have direct way of triggering stop and since some of the signals are edge sensitive and rely on feedback of previous message, things could easily go wrong. and that would mean more commands to cancel and start again - while this thing is still moving relentlessly.
the timing diagrams in KUKA manual show the sequence of signal transitions in normal (expected) cases. things on the time diagram are in order of time progression and it is not to scale, it is compressed to fit the page. but for discussion we could pretend that each of the vertical dashed lines is 1second increment just to easier communicate things.
normally this is set to input 1025 in all cases except when robot is in EXT mode because that is when decisions are done by PLC so PLC need a way to say stop. This is why when planning to use EXT mode, this signal should be changed from input 1025 (always true) to some other input that PLC can control.
optionally one can disable move enable check. in this case message you saw would be gone even if move enable is still on input 1025 ...but ... obviously this is not recommended and should be used only in special case after considering all risks and potential effects.
then it starts by operator dealing with safety ($ALARM_STOP and $USERSAF are true) and following that PLC setting initial signals ($MOVE_ENABLE, $DRIVES_OFF). this part is compressed so it looks like at "0.7sec" all of them are instantly on. in reality they do need to get to that state but edges do not line up that perfectly. and the edges do not matter here - these signals are level sensitive (no edge sensitive)
what remains is telling to robot which program to run. so PLC need to set the PGNO to some value, verify that robot sees the same thing and then turn on PGNO_VALID. at that moment, CELL calls one of the user programs. when PLC sees that, it need to turn off PGNO_VALID,,,
I'm now realizing that I may not have understood the non-synchronization of WorkVisual's Configuration and Programming workspaces, which may have caused the resetting of my changes. I will be mindful of this when I give it another try. But basically, I changed it in on the smartPAD under Automatic External Inputs.
Yes, I found that post, and I have downloaded the PDF of your sample code. I found your explanations of level-sensitive and edge-sensitive very insightful. Although I was already familiar with "rising edge" and "falling edge" of signals in general, I hadn't noticed/realized the edge-sensitivity of some of these AUT EXT signals in the signal diagram!
Could you please explain a bit more about generating the 10Hz clock? I'm not yet able to implement something like that on my PLC. I'm also using FBD, and some of the ladder logic is lost on me. Should I generate pulses in a SFC and loop back based on whether or not $PERI_RDY has been turned on?
well... don't you think it would be a good idea to share what that PLC is? also this is a robot forum, not a PLC forum. finally working with timers is basics regardless of platform and forum is not meant to replace formal training. if one does not understand basics, automating industrial robotic cell is not something to start learning on.
most PLCs already have flags or free running clock. in some cases one may need to map it to some variable range. there could also be ready instructions that generate pulse train. and finally nothing stops one from making own clock using timers or counters or whatever...
clock is simply signal that repeats at some rate. in software this is usually done by using timer, specially when accuracy is required. also on some systems timers may be precious resource (old or small PLCs), therefore it is always good to know how to solve something in more than one way.
in this case condition is inverted (using NC contact) but as long as there is inversion at one place (could be coil at least on some PLCs) and code is processed continuously, there will be some oscillations.
such signal is asymmetric, Timer.Q would only turn on for an instant (one PLC scan). so duty cycle is VERY low. one option is to add another timer or flag to keep track of things - the goal is not to use this asymmetric signal but that is convenient intermediate step to produce 50% duty cycle.
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