Monitoring 2 doors with 1 Stack Light

Jody Boehs

Member
Join Date
Apr 2018
Location
Oklahoma
Posts
2
Hello,

I am fairly new to PLC programming. I have wrote a few programs, but still learning.

I am part of a volunteer fire department. We are fixing to build a new station soon. I want to install a PLC to operate all the overhead doors (8 of them). Due to safety reasons I will be installing stack lights between each of the doors. Now comes the confusing part (for me anyway). I want the stack light on either side of each door to reflect the status of that particular door. For instance, if Door 1 is open, then the lights on either side of door 1 would display the same status. BUT, I need the same thing on door 2, I need the lights on either side of door 2 to reflect its status.

If this is even possible then door 2 would be interrupting the status of door 1 shown on the light between door 1 and 2.

My original plan was to have:
RED Rapid flash - Opening or Closing
RED Steady ON - Stopped while in motion
AMBER Slow flash - Opened but auto closing in set amount of time
BLUE Slow flash - Opening or Closing
BLUE Steady ON - Open
GREEN Steady ON - Opened or Closed

I this even possible or will I need separate lights for each door?
 
Its hard to make a single stack show the status of more than one door. Perhaps better to put the stacklights above each door rather than between them?
You also need to resolve the discrepancies in your specification for the condition to be indicated by each color. For example, your definition of red rapid flash and blue slow flash is the same. Also if green steady on denotes opened or closed, what does blue steady on represent? Is there a difference between open and opened?
 
Seems overly complicated for some doors. 6 states is a lot to remember. Can you not reduce to say green and red, or green, amber and red.


KISS is normally the best approach.
 
Are you really working for an FD ?

I'm asking because this sounds a lot more like a homework problem than a real application.

Most firefighters are reasonably alert and can determine important things like "is this door open" or "is this door in motion" without the assistance of an indicator lamp.

In addition, beacons and strobes and lamps have really important roles in a firefighter's life.

Where I live, blue strobes mean toxic gas leak (H2S or chlorine) and I don't want a firefighter to have to modify her at-a-glance instinct about breathing apparatus in order to determine that a door big enough to admit a firetruck is in fact open.

I do have auto-closing doors in a factory where I work. All of them use a single amber rotating beacon to indicate that they are in motion or about to close. I've never seen a door that wasn't an airlock that needed an indicator to tell you it was closed.

It's OK to pose this as a hypothetical question, or as a homework question, or as an exercise in standard colors and functions of indicators.

But I would recommend strongly against actually putting functional color coded beacons on a fire station for the purposes of indicating door status.
 
Are you really working for an FD ?

I'm asking because this sounds a lot more like a homework problem than a real application.

Most firefighters are reasonably alert and can determine important things like "is this door open" or "is this door in motion" without the assistance of an indicator lamp.

In addition, beacons and strobes and lamps have really important roles in a firefighter's life.

Where I live, blue strobes mean toxic gas leak (H2S or chlorine) and I don't want a firefighter to have to modify her at-a-glance instinct about breathing apparatus in order to determine that a door big enough to admit a firetruck is in fact open.

I do have auto-closing doors in a factory where I work. All of them use a single amber rotating beacon to indicate that they are in motion or about to close. I've never seen a door that wasn't an airlock that needed an indicator to tell you it was closed.

It's OK to pose this as a hypothetical question, or as a homework question, or as an exercise in standard colors and functions of indicators.

But I would recommend strongly against actually putting functional color coded beacons on a fire station for the purposes of indicating door status.

+1

I do a lot of work for a major refrigeration contractor, and every single plant has multiple blue flashing lights which mean "ammonia leak detected". Hugely important for firefighters to know about the presence of a highly explosive gas when coming onto a site.

If anything, I'd just have red solid for closed, green solid for open, and amber flashing for in motion. But I agree with Ken overall - the fewer flashing lights you put in a fire station (other than the "there is a fire" flashing lights), the better.
 
Hello,

I am fairly new to PLC programming. I have wrote a few programs, but still learning.

I am part of a volunteer fire department. We are fixing to build a new station soon. I want to install a PLC to operate all the overhead doors (8 of them). Due to safety reasons I will be installing stack lights between each of the doors. Now comes the confusing part (for me anyway). I want the stack light on either side of each door to reflect the status of that particular door. For instance, if Door 1 is open, then the lights on either side of door 1 would display the same status. BUT, I need the same thing on door 2, I need the lights on either side of door 2 to reflect its status.

If this is even possible then door 2 would be interrupting the status of door 1 shown on the light between door 1 and 2.

My original plan was to have:
RED Rapid flash - Opening or Closing
RED Steady ON - Stopped while in motion
AMBER Slow flash - Opened but auto closing in set amount of time
BLUE Slow flash - Opening or Closing
BLUE Steady ON - Open
GREEN Steady ON - Opened or Closed

I this even possible or will I need separate lights for each door?

Questionable light scheme aside, you'll still have a hard time understanding what's going on if multiple doors are opening and closing next to each other. I like the idea of a stack above each door, rather than on opposite sides.

Otherwise, it's a matter of timers triggered by open close commands and flashing some lights. It's not going to be a weekend project, assuming you are doing the wiring, too.
 
As a few mentioned, you are over-complicating matters and I say reinventing the wheel. I would start by looking at the end users, who are the lights for and when will they refer/look at it.
In an emergency, they won't have time to decipher all those signals and remember what they mean. It's an overhead door not a ****pit!

Traditionally, the lights for overhead doors work as follows:

Red:
1- Is anywhere but fully open.
2- Light timer (not timer to close) timed out which means the door is about to close or is already closing.

Green: Door is fully open and light timer hasn't timed out.

There are dual timers. One timer to change from green to red and a second timer to close after red light has been turned on.

Most commercial opener manufacturers produce openers with controls to operate traffic lights.

Some fire halls have additional light indicators in their control room to indicate door status on their boards and they function exactly the same.

There are liability issues that need to be considered before embarking on such a task.
 
I agree, this looks like an overblown solution to a non-existent problem. ;) Typically, the overhead doors on a fire station will have one or more single red lights on the side to indicate that the driveway is for emergency vehicles only and no parking is allowed. Any other lights can create confusion. It may even be a requirement in some code. Consult your architect.

I've only noticed the red/green lights on loading docks, and only on the side where the driver can see them in the left mirror.

Mike
 

Similar Topics

Our punch press has a SLC500 with HELM weight module (HM-604-WM) for tonnage monitoring. The operator enters the weight range on the HMI, which is...
Replies
9
Views
141
Hello, I have been trying to figure out how to connect to and monitor a DLR that is on a remote rack from my PLC. The local has a 1756-L81E and...
Replies
0
Views
80
Good day, we have 15 analog inputs, we need to log the data in excel and monitor these values through web browser. We're planning to go with Delta...
Replies
1
Views
77
I have several plc’s that I’d like to monitor Into our SCADA when the comms break or plc faults. These are (SLC-505 & Compact Logic PLC’s) I...
Replies
6
Views
724
Hi everyone using the profidrive in s7-1200 motion control under position monitoring :the tolerance time is the amount of time that the axis...
Replies
0
Views
522
Back
Top Bottom