h a l f b a k e r yI didn't say you were on to something, I said you were on something.
add, search, annotate, link, view, overview, recent, by name, best, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
In many industrial applications, it is necessary to lock out power to a piece of equipment before servicing it. Shutting off the power isn't good enough; the power switch must be locked "off" using a padlock whose key is held by the person working on the equipment.
In many environmental situations,
this is handled by having a "lockout board" from which hang a number of color-coded locks with their keys installed. A worker who needs to lock out a piece of equipment will take a lock, put it on the device in question, and take the key. When he's done, he'll remove the lock and return it to the board.
While this approach is certainly workable, it does have two disadvantages:
-1- A worker must keep the keys for all lockouts he controls.
-2- Inspection of an installed lock will give no clue who holds the key.
What I'd propose would be a padlock which is designed so that it can auto-adapt to any of a few dozen keys. When not in use, the lock would be open. Inserting a key, closing the lock, and removing the key would "set" the lock to use that key; unlocking it would require reinserting the key. As an additional feature, the lock could incorporate a readout showing information about the identity of the key that was used to secure the padlock.
One possible implementation would be to use a cross between a settable combination lock and a tumbler lock. Inserting a key would 'dial the combination' on the interior mechanism, and opening the shackle would allow the combination to be reset. To allow easy identification of the employee responsible for securing the lock, one or two wheels/sliders would be exposed to a window allowing that part of the combination to be seen.
[link]
|
| |
I see what you're getting at here. |
|
| |
However, I'd point out that any situation with which I am familiar has the worker getting assigned his/her own (set of) lock-out locks and keys, the locks being engraved with the worker's name and the corresponding key number. I believe this effectively solves the problem illustrated in your #2 point. |
|
| |
As far as your #1 point goes, that's an inherent aspect of keys/locks, it seems to me. |
|
| |
This is certainly workable with an electronic lock. If I enter my (secret) number on the keypad, the lock closes and a panel displays my employee ID. |
|
| |
In more sensetive applications, the whole lock/key issuing system is tied in with a permit-to-work documentation trail as well - it's laborious but does assure a high level of system integrity. I'd be very loath to advocate any change that might move away from this type of highly supervised system. But I see the point, and it's a good one for lower-risk applications. Sorry, but I can't quite bring myself to give it a croissant yet .... |
|
| |
angel: even easier if you use fingerprint recognition. Though perhaps hands get too dirty in an industrial situation...? |
|
| |
Wouldn't know. Long time since I was in an industrial situation. |
|
| |
Why not just get the workers to sign for the locks and keys when they take them from the communal cupboard? |
|
| |
Well, one guy may need to have several systems locked out at the same time. |
|
| |
I like the idea of the electronic padlock. Rather than typing a code on a keypad, I'd prefer a card swipe. You could lock as many padlocks with one card as you like. Plus, you could lock one padlock with as many cards as you like. That way, if Bud and Bubba are both working on the power line, but in different locations, each can swipe his card through the lock. The lock remains closed until both Bud and Bubba swipe their cards though a second time. An LCD can show the number of outstanding lock requests and the ID number of the most recent requestor. This feature would be very easy to implement in software. |
|
| |
Until a hardware solution exists to track lockout owners automatically, I guess people will just have to resort to procedural methods of tracking. Either have an info tag accompany the lock on the equipment, or else have a lock checkout system with a log book of who is currently using which locks. Both methods are in wide use at various locations. |
|
| |
The difficulty with having locks pre-assigned to users is that it becomes necessary to issue each user the maximum number of locks they'll ever need. In some cases, a user may very seldom need more than two or three, but in one particular case might need a dozen. If multiple users wouldn't need a dozen locks all simultaneously, the communal lock approach might be good. |
|
| |
Actually, if safety regs would allow for electronic locks in these applications, they could have substantial advantages over conventional ones. For example, if a worker installs a conventional padlock in a breaker-panel lockout spot without using a multi-lock adapter, it may be impossible for someone else to attach an additional lockout. An electronic lock, by contrast, could keep track of multiple active lockouts. [My mechanical lock could be adapted for that also, though operation would be a bit less intuitive and the mechanism would increase in complexity with the number of lockouts.] An electronic lock could also provide logging abilities. |
|
| |
Include in the padlock a hole through which the shackle of another padlock may be placed. When another padlock is inserted in this hole, the lock may be unlocked but will not actually open until the other padlock is removed. |
|
| |
Sorry, but I have to advise against anything involving card swipes or digital codes .... NEVER USE SOFTWARE IN A SAFETY CRITICAL APPLICATION. By which I mean detonator systems, HV switching lockouts, and anything involving nuclear material. |
|
| |
It may seem stupid but when you've had experience of this stuff, you'll be reasured when you work by the knowledge that the control system is blocked by a piece of 8mm hardened steel bar, and the only key is on a string round your neck. Safety regs specifically exclude the use of electronic systems for a number of very gooAbort, Retry, Ignore ? |
|
| |
Current drive is no longer valid> |
|
| |
Unable to find COMMAND, system halted. |
|
| |
General Protection Fault ........... |
|
| |
Unless, of course, the software is necessary for responses that are faster than a human can react, such as fly-by-wire systems, flight directors, atmospheric re-entry systems and anti-skid controls. |
|
| |
The point is that there are going to be more and more situations where it will be considered unsafe for a human to have control and only software will be able to fulfill the role. |
|
| |
fly-by-wire => Die-by-wire. No thanks. |
|
| |
But actually, this isn't about control; it's about disconnecting control (Like cutting off HAL's cabling in 2010). It's one thing to have the software in control most of the time BUT you still need a manual override/hard interlock. It's not about speed of response - it's about ensuring no response at all. |
|
| |
I've seen software, and I've seen clunky stuff with big levers and wires and cogs, and when you're dealing with the real Scary Stuff the levers and cogs are definitely better. |
|
| |
Soory it already exists. CHeck out Cyberlock by Videx |
|
| |
What if it used a traditional key but the electronic system
was only in place to log the "key number" and change the
code when a new key is inserted-the actual locking is still
mechanical and once it's been set, the electronics by
themselves cannot actually UNLOCK the lock-they can only
log/rekey the lock. The actual keys for this locking system
would be unique, and have #s that corrospond to what
would appear on the lock if that key was set to it. |
|
| |
For example, turning one direction when unlocked will
lock the lock, but only if that key is already "set" but
turning in the other direction while unlocked, possibly
while holding a button, would set that key to the lock and
show a log of the key #. |
|
| |
For multiple-employee locking situations, there could be
2 key holes, which when locked, will remain in one
direction until unlocked, like a filing cabinet or soda
machine's lock would. Only one key hole in the locked
position is necessary to lock. |
|
| |
That way, if the electronic system was malfunctioning, the
batteries ran out, whatever, the lock would still be locked,
and could still be opened with the same key. |
|
| |
too complicated. In industrial situations a combination of locks and safety interlock devices are used. Here is how i believe it works: Each primary carries a key with their name on it. Any one of the primaries can shut down the circuit. The circuit can also be shut down using an emergency relay which can only be reset by inserting the supervisor key. When a key is inserted a interlock bar pops out of the breaker locking the key in place, indicating who disabled the circuit Whomever is doing the service takes the unique interlock bar with them and returns the bar when the service is finished, returning the bar allows them to retrieve their key. With out the uniquely shaped bar the circuit cannot be energized. |
|
| |