v0.31 Talk:Pressure plate

Hatches won't open when there is water on them

It seems that an older version of hatches was able to open when there was water on them, but not now. Has this changed? Because the "water on hatch resettable system" does not work - thus it's not current. Am I missing something here?

Pressure plates not activating. Bug? (Well no, but...)

Recently i secured my fort with a fine bridge-fall-trap (plates are activated by everything but citizens) ... like i always do ... aaand got roflstomped by some gobos that were quite unimpressed by the not moving . Strange enough, i loaded an older savegame and rebuild the pressureplates this time with "citizen activate" on, but the bridge didn't open when my dwarves were stomping over the plate. So i connected a lever, bridge opened like normal. I start to think that pressureplates are not working correctly. -- unpaid lamer

It seems that not the plates themselves are bugged ... but the MIN number is cut away so that the weight setting of 100k seems like the weight setting for 10k. This makes up for nice surprises and fun. -- unpaid lamer

Pressure plates getting stuck. Bug?

I have recently built a system for an impenetrable, self regulating reservoir. This involves a river flowing through a diagonal-only pressure neutralizer, past a raise-able bridge, through some fortifications and on to a re-usable pressure plate set for a depth of 5+/7. The water then drops a level to my reservoir and goes through a second diagonal-only pressure neutralizer.

The idea is that if the water is less than 5/7 then the fortifications make it un-enter-able to water monsters (including building destroyers). When the water reaches 5/7 the bridge is raised creating an indestructible wall that stops the water flow and prevents building destroyers passing the flooded fortifications. When run it works for about 20 rounds after which the bridge gets stuck in the raised position and the reservoir evaporates, still not even containing a layer of 1/7 water.

I was planning on using a similar system at a depth of 2/7 to create a continually self-activating series of death traps, thus avoiding the 'Trap Avoid' tag.

Does anyone know why my automated, self-regulating, on-off water switch isn't working?

Just Another Guy. 8:17 UT

Missing Entries

I've noticed there's no goblins on the weight list (arguably one of the most important would-be plate-walkers). A quick second peek revealed that slugmen are missing, too. Someone should cover any missing creatures or, at least, goblins. --Bronzebeard 10:35, 29 April 2010 (UTC)

I will be writing a script that will read the weights. It's difficult to write them out, because things change weights based on how old they are. I'll be thinking of ways to represent this, but II'll keep it as it is right now. --Jargle 23:19, 10 May 2010 (UTC)

I finished importing all the weights info from the raws- THESE NUMBERS ARE IN FACT ACCURATE. I think I deserve to be angry if people change them since I spent 5 hours on this today. I guess I'm just grumpy. Jargle 07:09, 21 May 2010 (UTC)

Floors

There's some confusion over what kinds of floors plates can be built upon. Just confirmed that they can be built on constructed rock block floors, though others have reported that it doesn't work? Is there some discrepency between 31.03 and .04? Minus 03:33, 22 May 2010 (UTC)

I'm not sure. I've never had any trouble constructing them on any kind of floors. I don't think you can construct them on a road, though, which someone might easily mistake for a constructed floor. I'll have to check sometime. Uristocrat 03:13, 3 January 2011 (UTC)

Settings

Could we add a section explaining the details of the "Resets" vs. "One use only" settings? I'm still learning and I'm wondering if "One use only" plates can be manually reset after they have been triggered. I'm sure others will wonder as well!

A one-time use pressure plate disappears the instant you step on it, and in my experience it also destroys all of the mechanisms contained within it, so don't use masterwork mechanisms. --Quietust 20:20, 4 July 2010 (UTC)

What does "Citizens do not trigger" affect? Your dwarves, obviously, but what about pets? And what about traders/diplomats? --75.183.164.142 00:04, 9 December 2010 (UTC)

I know this question is old, but in case anyone is reading this page and still curious: if "Citizens do not trigger" is activated, pets and other tame animals DO NOT trigger. I'm testing tonight for traders and diplomats, and will edit this with my findings. --Asfghn 07:42, 4 April 2011 (UTC)

Units of Measurement

The article does not mention the units of measurement for weight. It certainly isn't pounds or kilograms, a typical goblin doesn't weigh fifty-thousand pounds. It is confusing to follow with meaningless numbers (unless they truly are meaningless numbers) --Gamli 22:35, 11 Sept 2010 (PST)

An interesting point; readers would benefit from a reference point. Perhaps the article would be improved if the weight list mentioned up front that that humans weigh 70,000 units and dwarves weigh 60,000 units. -Coaldiamond 03:14, 18 September 2010 (UTC)

I could be wrong, but the unit of measurement might be grams (not kg). That gives you 70kg for humans and 60kg for dwarves, which is approximately reasonable. Uristocrat 02:53, 3 January 2011 (UTC)

Instant triggering

I tested Pressure Plates a bit today, and it seems like they trigger instantly, at least for Hatch Covers. I didn't want to edit the article without more testing having been done first. Can anyone confirm or dis-confirm my suspicion?--CaveIn 17:00, 17 September 2010 (UTC)

That's how they've always worked - stepping on a pressure plate is exactly like pulling a lever, though stepping off of a pressure plate has a 100-tick delay before the trigger resets. --Quietust 17:33, 17 September 2010 (UTC)

Reversing Signal

Since activating a pressure plate sends an ‘open’ signal to its connection, it would be possible to send a ‘close’ signal by connecting the activation pressure plate to a hatched room filled with water with a different pressure plate set to 7/7.

Location 1

|----X----|
|---------| 'X' is a floodgate/door/bars
|----^----|

Location 2

-----------
|~ ~~^~ ~|
|~ ~~ ~ ~|          'c' is a hatch over a hole
|~ ~~c~ ~|
----------

The room at location 2 is full of 7/7 water, keeping the pressure plate activated keeping floodgate at ‘X’ open. When the pressure plate at location 1 is activated the room drains stoping the activation and therefore closing the floodgate ‘X’ at location 1

• Bonus -Use magma for more fun!?

Haydosss 12:06, 7 October 2010 (UTC)

backwards floodgates

Flood gates and pressure plates can only be used to open a gate when there is water. Why would anyone want to open a floodgate when there is water. Real flood gates are for stopping floods. Which means they're open if there's no flooding in an area, and closed if there is a danger of flooding. In DF, floodgates open when there is plenty of water to flood with, and close off the water if the place is dry. If you wanted water to flow when there is water in an area you might as well use a hole. That's how holes work. When there's water, water goes through them. When there is no water, not water goes through them.

In older versions you used to be able to set a pressure plate to open a door when the water level is low (0-3 for example). I haven't been able to get this to work in the latest version (the door closes, but then won't reopen). Is this a bug, or something I'm doing wrong? --Chris 14:43, 17 May 2011 (UTC)

Trap avoid?

Do creatures with trap avoid activate pressure plates? It's not mentioned in the article, and it probably should be. --Cam94509 21:28, 11 May 2011 (UTC)

They do not. I've edited the page to say so.98.203.173.56 09:05, 12 August 2011 (UTC)

Timing

I've made an edit that's probably going to be a little controversial regarding the exact timing of pressure plate signals. Anticipating this, I recorded my experiment. You can step through it, tick by tick. It's available at http://mkv25.net/dfma/movie-2363-timingdetails

This is done entirely with creature logic; I believe fluids should work similarly, although it does leave me at a loss to explain exactly how fluid-based repeaters function (maybe it really does take a tick for fluid to move through a pump?)-- and plus, before I did this experiment, I believed that doors, bridges, and gear assemblies should all have identical triggering timing! I sure hope somebody figures out a way to do a similar test with fluids and posts their findings here.

Likewise, I believe that these findings should be extensible to levers-- but there's no way that I can think of to do that test. Based on uncertainty regarding levers, I'm not going to edit that page. I am, however, going to have to go through a bunch of pages I've modified and correct them (for the third time, as each experiment left me doubting the last, and I reasonably expected timing to not depend on device type-- I'd make a change when experimenting with one type, then have to revert when the next type of furniture didn't behave the same!)