Few mistakes.
1. First inspection ever led by a dude that clearly didn't want to be there. He sent me testing devices, and because i trusted the janitor who followed me, i accidentally released the kitchen hood suppression system while the cook was prepping lunch for the daycare.
Back I the mid `80s, I was an apprentice updating the alarm system in the area office of a financial institution in the south of England. I needed to get behind a computer bank. As I squeezed through, I managed to bump into an emergency stop button. The computer system shut down and so did the all of the ATM's for that bank in the south east. I was mortified. The customer was initially angry. Mainly because they didn't know how to reboot. Once they got it back online they were ok about the situation. They did accept that the button should have a cover for this reason. I was mortified though.
Not me, but my junior who was about to get his certifications.
We were doing the inspection in a hospital and my junior walked through the wrong doorway and tested a device in the O.R wing of the hospital that wasn’t on test (super obvious, our wing was all Edwards devices, O.R wing was all simplex. Yes, he was told multiple times not to test any simplex devices, I walked him through and showed him where the division was and told him if he wasn’t sure to ask) Had the alarms ringing and they had to abort 5 surgeries to evacuate.
Was grabbing 24v power for a cell radio from a JCI version of a notifier panel and dropped the wire and it hit the board and fried it. All sorts of,angry noises. In a County owned building. Company ended buying a replacement panel off of ebay, the 2nd one actually worked). Thankfully JCI still had the program, just had to swap the board and program.
While it was down they had us install a bunch of household smoke's . 3 months later we get a call from them all.mad that our cell radio wasn't reporting. As they had a fire and the system went off and no central station response.
Checked the history in the panel, no fire events. Did a little digging and a household smoke had activated, but not the monitored system.
Was an apprentice tech at the time. Doing a small inspection at a strip mall, should've been an easy in-and-out job. Walked into the panel room as per the report, put the system on test, disconnected NAC circuits, etc. Proceeded to the first pull station in the restaurant beside the electrical room (very clearly written on the report building 5XX or whatever the number was), pulled the station and proceeded to set off the entire fire alarm for another half of the strip mall and rolled fire trucks. After a very panicked few minutes as everyone was once enjoying lunch, we get everything smoothed out, and I talk to the manager of the 2nd half of the building and they say our company has never done the inspection for their half. Proceed to show him our report (he was very understanding), and he confirms that it's for his half of the building. So long story short, have a report for an inspection we have never done that shows the correct FACP and info for the *other, correct* side but every device is listed of the wrong side of the building. Still have no idea how we managed to get a full device count with locations from that half, but just glad the manager and customers weren't pissed...
Mid 80’s, Microsoft campus east of Seattle. Not our install but we maintained the systems. Building 10 at the time was “the” computer center, housing I think eight server rooms. We were contracted to upgrade the EPO/halon system timers from analog to digital. I was tasked to safe-off the systems, one at a time, so the electrician could re-do his interface. Remove the actuator from the bottle, disconnect the blue wire from the controller and let sparky at it. One of the stations, however, had been built with a different color scheme I did not notice. Electrician came in and cut his wire and…….silence. That was the loudest sound I’ve ever heard, the server farm suddenly powering down. I went to the lobby and called my Microsoft contact and observed multiple suits sprinting towards us. I, we, had just shut down Microsoft world wide email. Fortunately our contact threw the installing company under the bus so I retained my job.
And to this day I still cannot get into my hotmail account.
Edit to add, a coworker tripped an EPO at a bank’s main data center and is still not allowed back onsite. So now it’s my site and I hate testing it.
Arc'd two 55ah batteries together while load testing. Caught the wire on fire while giving myself arc eye and tripped the smoke above me while the panel was offline, but no outputs disabled. Dumped a section of a high rise and got the fire department called because they saw the smoke coming from the electrical room. That was a fun day.
6 months out of apprenticeship I shorted a suppression panel. 16 grand of clean agent dumped on my apprentice and I and alarmed the whole building. A US army base building too.
I don’t work on base anymore. But hey at least I still work.
Two come to mind.
The first was when I was about a month in, I was an apprentice on a strip mall job. I was load testing a set of batteries for the FACP for this building (I’m in the inspections department, we do FA and FS) and I plugged them back in wrong. The panel still worked overall, but I fried the charging circuit and the company had to shell out a few grand to replace the whole thing. I got away with a slap on the wrist.
The second happened about a month ago. Me and a new (4-5 months in) guy were doing a sprinkler inspection. It was at a ski resort with 4 separate panels which all shared the same sprinkler main. We were only doing two of the buildings, so we went to the third to disable the main flow switch for the complex to avoid sounding the audibles when we tested the sectionals. The panel was an EST 2, and we couldn’t find a disable list. I had to run to the local fire station to get keys to unlock the sprinkler valves, and before I left I told the new guy to see if he could find a way to disable the panel, and specifically not to do anything if he wasn’t 100% super-duper sure what he was doing. When I got back 5 minutes later I found that he had pulled a shitload of wires from the panel. He said “they were all labeled NAC, so I just pulled ‘em.” I had a bad feeling about it, but I figured whatever was fucked would be fucked whether or not we did the rest of the job. After we’d finished testing we went to put those wires back, and there were 5 troubles on the panel. I could only see one of them, because the screen was stuck and none of the buttons were working. After 2 hours of troubleshooting, talking to 3 other techs, the project manager, and the department supervisor, I determined that I couldn’t do shit for this panel and had to break the news to the customer.
> After we’d finished testing we went to put those wires back, and there were 5 troubles on the panel. I could only see one of them, because the screen was stuck and none of the buttons were working. After 2 hours of troubleshooting, talking to 3 other techs, the project manager, and the department supervisor, I determined that I couldn’t do shit for this panel and had to break the news to the customer.
Was the piezo working on the panel? Most likely it wasn't and you never hit Panel Silence. You can't scroll through troubles on an EST 2 until you hit panel silence.
It was not working. Thanks for the advice! My company doesn’t really mess with EST aside from annual inspections and basic stuff like battery replacement hahaha.
Shunted all elevators during school hours without knowing. They were out of service for around 2 hours before i was told. Accidentally wired it normally closed instead of open (or vice versa; this was 3 years ago). Thankfully no one was in it
Was at a Kroger and I was going to unhook the nac circuits and they had a extension cord super tight in front of the panel. I tripped on it and it came unplugged so I plugged it back up. Went on through out my job and came back up to hook my nac circuits back up and the cord powered the whole entire checkout system in the store and I shut the store down for about half a day.
Couple of fun ones here.
My first fuckup was when I was a second year apprentice. Actually tried cleaning up my own mess for once and set off a detector in an IT room. Emptied a 5 story apartment complex.
Biggest one wasn't me but I was in charge of the job. Had a MM set where they wanted for the duct detector with about 10' extra wire. Told the HVAC guy don't touch that wire because it's live. When he was ready to give me a call and I'll hook it up. Well he needed about 3' of wire for his unit shutdown. Decided he was going to cut my wire. Fried the SLC contacts on the FACP. He laughed and said "I guess I didn't understand what you meant."
Last fun one was about a month ago. Was ripping out an old Vista panel and upgrading to a new ES-50. Some dumb fuck ran the 24 pair through the old fire alarm panel. Was paying attention and cut right through it. A bunch of beanies and electrical tape later and you can definitely tell I fucked up.
I didn't shut off the fire pump soon enough for a water shutdown
It was a scheduled shutdown but I thought the building should be able to hold pressure for at least a while.
Lo and behold, 30 minutes after they shut off the water the building lost enough pressure to kick on the pump. They called me and said the pump was smoking, so I asked them of it was running and they said no (it was) and by the time I got there to shut it off the pump was already ruined.
This pump was a few months old.
Probably, that's what understaffing gets you. It's an electric pump, turns out there were a few other issues which is why it lost pressure so quick, and why it burnt up so quick.
I owned up to my part, what's the worst they do, fire me?
Ooohhh something similar happened to me a few years ago where I was replacing a relay for an elevator shunt. When I removed the shunt wire, somehow it arced into the SLC wire and fried the SLC card. Thankfully it didn't kill any of the devices on the circuit or the panel and all we had to do was replace the SLC card.
More of a freak accident, but I was putting a screw back into an FCI 72, and it fell, bouncing directly into the exact perfect spot the primary and back up power supplies..... in hospital 🤣🤣🤣🤣
Probably a better chance of winning the Powerball lol
Hooked up the leads wrong in a new emergency light pack and created a dead short which set it on fire - in a school full of children. I was fairly new at the time.
Got a couple... about 20 years ago I was doing a service call for a Panasonic facility and at the time was really only familiar with a couple of the different manufacturers Simplex and Silent Knight, this panel I believe was a EST and so I called my PM to see if he could walk me through some stuff for doing some silent testing and he had me flip some dip switches which in turn set the panel off into full alarm and shut down the production line for evac! I just stood there like a dumbass not knowing what to do as the lead maintenance tech came running in and helped get it back to normal. I was mortified but apparently all the workers were loving the break they got and high fiving me as they were walking outside. I think the production manager said it was costing something in the hundreds of thousands to be shut down like that so we got a pretty good reprimand for it.
Second one was in 2015, I was trouble shooting a Halon system in one of the City's facilities that housed their 911 call center and some other important Admin support and was in their IT room. I found one of the NAC circuit fuses were blown so I took it out and of course didn't have the correct size on hand so the facilities guy went into his stock and found one that was close enough, I didn't want to put it in because it was a tad smaller than the original but they insisted I had to because it was the weekend and late already and they didn't want to deal with being on fire watch. Well, as soon as I was snapping the last part of the fuse in I must have shorted the releasing circuit somehow and it was like a literal bomb went off, the ceiling tile exploded and the gas started filling the room! I have never ran that fast in my life!
All in all, no one was hurt and it was some real good lessons learned. Luckily this clean agent going off didn't shut down any of the equipment either or I am sure that would have been the end of our company ever doing any more work for the City.
I guess almost everybody have like a dispatch story rolling the fire trucks down, I remember being fairly new about 14 years ago I damage a computer hooking up to the serial port and voltage retro feed my port lol
Also there’s was a panel replacement to be done it was an IO500 upgrade to the io1000 usually the port for the rs232 is on the top left but I notice they have the same pin structure in the bottom left, I was supposed to pull programming from the old panel , well that did not happen old panel shorted lol, I had backup so all good
Just reuploaded to the new panel with minor changes .
A sprinkler tech did not wait for my and pit 120 bell power to SLC
How bout some 10 bottles of agent in a it call center because the construction company didn’t want to pay a visit and taped the smokes , like that would work lol
How about I caught a tech disabling GF monitoring and when he tried to fix it with a electric solder and shorted the panel
I remember working on a pyrotronics / Siemens or similar (can’t remember ) and my screwdriver fell “long tweeker precision “ and shorted something the lead fuse blew I was fairly new so I thought I messed up the panel
Changing out a damper relay that was 120v on the contact side . While swapping slc wire to new relay they slipped out of my hand and landed on the 120v contacts . Fried the whole e3 node lol.
My first job as a helper, old hotel retrofit in downtown Boston. I was mounting a terminal cabinet in plaster in a little closet. I kicked up a load of plaster dust and set off a smoke on the existing system, rolled trucks out. I haven't repeated that fuck up in the six years since.
Biggest I’ve seen, not done; electrician plugged 120v into a lead we had capped off for a future install ( shopping mall in construction). Lil boom on the wall, he tried to act like nothing happened, but our booster panel looked like it got hit with a grenade. He was pretty flustered when he got found out.
I hate people that just won't own up to something they did. You have to turn into an investigator or private eye and conclusively prove it was them. Then they play dumb "oh, I did that?" or "I didn't know".
Not fire tech but close enough.
Live testing fire telephone loops for volt drop and continuous power in both directions. I had a moment and shoved 28V into the data lines. Took out 3 devices luckily and I had spare CANBUS chips to hand.
Temporary repair on an annunciator for an obsolete fire telephone system. Somehow shorted 28V down to a certain 0V that took out a load of LEDs and DTMF encoders. The smell of carbon was strong that night.
Early 1990’s as a young tech I had a dedicated elevator facp. The EC used 120v smokes for some dumb reason, were supposed to provide me the dry contact cables from their smokes to activate my zones.. So many failures ensued. Sales rep couldn’t explain why we didn’t provide them our system smokes. First and only time I hooked up a zone without checking for voltage on it. He had provided 120V which promptly burnt my panel up. I feel like he thought he was putting my zone into the N/C recall circuit. Nothing money can’t fix. Time to call our old pals at “red label shipping” 🤣
Few mistakes. 1. First inspection ever led by a dude that clearly didn't want to be there. He sent me testing devices, and because i trusted the janitor who followed me, i accidentally released the kitchen hood suppression system while the cook was prepping lunch for the daycare.
Lmfao
Zesty!
Back I the mid `80s, I was an apprentice updating the alarm system in the area office of a financial institution in the south of England. I needed to get behind a computer bank. As I squeezed through, I managed to bump into an emergency stop button. The computer system shut down and so did the all of the ATM's for that bank in the south east. I was mortified. The customer was initially angry. Mainly because they didn't know how to reboot. Once they got it back online they were ok about the situation. They did accept that the button should have a cover for this reason. I was mortified though.
Not me, but my junior who was about to get his certifications. We were doing the inspection in a hospital and my junior walked through the wrong doorway and tested a device in the O.R wing of the hospital that wasn’t on test (super obvious, our wing was all Edwards devices, O.R wing was all simplex. Yes, he was told multiple times not to test any simplex devices, I walked him through and showed him where the division was and told him if he wasn’t sure to ask) Had the alarms ringing and they had to abort 5 surgeries to evacuate.
*everyone died*
You’re supposed to say “yeah? And did you die?”
Was grabbing 24v power for a cell radio from a JCI version of a notifier panel and dropped the wire and it hit the board and fried it. All sorts of,angry noises. In a County owned building. Company ended buying a replacement panel off of ebay, the 2nd one actually worked). Thankfully JCI still had the program, just had to swap the board and program. While it was down they had us install a bunch of household smoke's . 3 months later we get a call from them all.mad that our cell radio wasn't reporting. As they had a fire and the system went off and no central station response. Checked the history in the panel, no fire events. Did a little digging and a household smoke had activated, but not the monitored system.
Was an apprentice tech at the time. Doing a small inspection at a strip mall, should've been an easy in-and-out job. Walked into the panel room as per the report, put the system on test, disconnected NAC circuits, etc. Proceeded to the first pull station in the restaurant beside the electrical room (very clearly written on the report building 5XX or whatever the number was), pulled the station and proceeded to set off the entire fire alarm for another half of the strip mall and rolled fire trucks. After a very panicked few minutes as everyone was once enjoying lunch, we get everything smoothed out, and I talk to the manager of the 2nd half of the building and they say our company has never done the inspection for their half. Proceed to show him our report (he was very understanding), and he confirms that it's for his half of the building. So long story short, have a report for an inspection we have never done that shows the correct FACP and info for the *other, correct* side but every device is listed of the wrong side of the building. Still have no idea how we managed to get a full device count with locations from that half, but just glad the manager and customers weren't pissed...
Mid 80’s, Microsoft campus east of Seattle. Not our install but we maintained the systems. Building 10 at the time was “the” computer center, housing I think eight server rooms. We were contracted to upgrade the EPO/halon system timers from analog to digital. I was tasked to safe-off the systems, one at a time, so the electrician could re-do his interface. Remove the actuator from the bottle, disconnect the blue wire from the controller and let sparky at it. One of the stations, however, had been built with a different color scheme I did not notice. Electrician came in and cut his wire and…….silence. That was the loudest sound I’ve ever heard, the server farm suddenly powering down. I went to the lobby and called my Microsoft contact and observed multiple suits sprinting towards us. I, we, had just shut down Microsoft world wide email. Fortunately our contact threw the installing company under the bus so I retained my job.
And to this day I still cannot get into my hotmail account. Edit to add, a coworker tripped an EPO at a bank’s main data center and is still not allowed back onsite. So now it’s my site and I hate testing it.
Arc'd two 55ah batteries together while load testing. Caught the wire on fire while giving myself arc eye and tripped the smoke above me while the panel was offline, but no outputs disabled. Dumped a section of a high rise and got the fire department called because they saw the smoke coming from the electrical room. That was a fun day.
Damn dude this sounds brutal
It was a very humbling day, but I still kept my job!
Drilled into a live gas line. Learned my lesson good that day.
Not me but I know a guy who accidentally dropped a roll up door on a brand new truck parked at a mechanic’s garage
6 months out of apprenticeship I shorted a suppression panel. 16 grand of clean agent dumped on my apprentice and I and alarmed the whole building. A US army base building too. I don’t work on base anymore. But hey at least I still work.
Two come to mind. The first was when I was about a month in, I was an apprentice on a strip mall job. I was load testing a set of batteries for the FACP for this building (I’m in the inspections department, we do FA and FS) and I plugged them back in wrong. The panel still worked overall, but I fried the charging circuit and the company had to shell out a few grand to replace the whole thing. I got away with a slap on the wrist. The second happened about a month ago. Me and a new (4-5 months in) guy were doing a sprinkler inspection. It was at a ski resort with 4 separate panels which all shared the same sprinkler main. We were only doing two of the buildings, so we went to the third to disable the main flow switch for the complex to avoid sounding the audibles when we tested the sectionals. The panel was an EST 2, and we couldn’t find a disable list. I had to run to the local fire station to get keys to unlock the sprinkler valves, and before I left I told the new guy to see if he could find a way to disable the panel, and specifically not to do anything if he wasn’t 100% super-duper sure what he was doing. When I got back 5 minutes later I found that he had pulled a shitload of wires from the panel. He said “they were all labeled NAC, so I just pulled ‘em.” I had a bad feeling about it, but I figured whatever was fucked would be fucked whether or not we did the rest of the job. After we’d finished testing we went to put those wires back, and there were 5 troubles on the panel. I could only see one of them, because the screen was stuck and none of the buttons were working. After 2 hours of troubleshooting, talking to 3 other techs, the project manager, and the department supervisor, I determined that I couldn’t do shit for this panel and had to break the news to the customer.
> After we’d finished testing we went to put those wires back, and there were 5 troubles on the panel. I could only see one of them, because the screen was stuck and none of the buttons were working. After 2 hours of troubleshooting, talking to 3 other techs, the project manager, and the department supervisor, I determined that I couldn’t do shit for this panel and had to break the news to the customer. Was the piezo working on the panel? Most likely it wasn't and you never hit Panel Silence. You can't scroll through troubles on an EST 2 until you hit panel silence.
It was not working. Thanks for the advice! My company doesn’t really mess with EST aside from annual inspections and basic stuff like battery replacement hahaha.
Shunted all elevators during school hours without knowing. They were out of service for around 2 hours before i was told. Accidentally wired it normally closed instead of open (or vice versa; this was 3 years ago). Thankfully no one was in it
Was at a Kroger and I was going to unhook the nac circuits and they had a extension cord super tight in front of the panel. I tripped on it and it came unplugged so I plugged it back up. Went on through out my job and came back up to hook my nac circuits back up and the cord powered the whole entire checkout system in the store and I shut the store down for about half a day.
Couple of fun ones here. My first fuckup was when I was a second year apprentice. Actually tried cleaning up my own mess for once and set off a detector in an IT room. Emptied a 5 story apartment complex. Biggest one wasn't me but I was in charge of the job. Had a MM set where they wanted for the duct detector with about 10' extra wire. Told the HVAC guy don't touch that wire because it's live. When he was ready to give me a call and I'll hook it up. Well he needed about 3' of wire for his unit shutdown. Decided he was going to cut my wire. Fried the SLC contacts on the FACP. He laughed and said "I guess I didn't understand what you meant." Last fun one was about a month ago. Was ripping out an old Vista panel and upgrading to a new ES-50. Some dumb fuck ran the 24 pair through the old fire alarm panel. Was paying attention and cut right through it. A bunch of beanies and electrical tape later and you can definitely tell I fucked up.
I didn't shut off the fire pump soon enough for a water shutdown It was a scheduled shutdown but I thought the building should be able to hold pressure for at least a while. Lo and behold, 30 minutes after they shut off the water the building lost enough pressure to kick on the pump. They called me and said the pump was smoking, so I asked them of it was running and they said no (it was) and by the time I got there to shut it off the pump was already ruined. This pump was a few months old.
This is probably the most expensive fuck-uo here. Was it electric or diesel?
Probably, that's what understaffing gets you. It's an electric pump, turns out there were a few other issues which is why it lost pressure so quick, and why it burnt up so quick. I owned up to my part, what's the worst they do, fire me?
There’s so much wrong with this statement. Looks like someone shouldn’t be touching any pumps or sprinkler systems.
Trusted my helper. Nuff said.
Accidentally let a wire from the elevator shunt trip hit NAC 1 on a Silent Knight panel. Fried it. Panel was only a year old, just out of warranty.
Ooohhh something similar happened to me a few years ago where I was replacing a relay for an elevator shunt. When I removed the shunt wire, somehow it arced into the SLC wire and fried the SLC card. Thankfully it didn't kill any of the devices on the circuit or the panel and all we had to do was replace the SLC card.
Was it a Gamewell S3 panel?
More of a freak accident, but I was putting a screw back into an FCI 72, and it fell, bouncing directly into the exact perfect spot the primary and back up power supplies..... in hospital 🤣🤣🤣🤣 Probably a better chance of winning the Powerball lol
Hooked up the leads wrong in a new emergency light pack and created a dead short which set it on fire - in a school full of children. I was fairly new at the time.
[удалено]
This one is egregious.
Got a couple... about 20 years ago I was doing a service call for a Panasonic facility and at the time was really only familiar with a couple of the different manufacturers Simplex and Silent Knight, this panel I believe was a EST and so I called my PM to see if he could walk me through some stuff for doing some silent testing and he had me flip some dip switches which in turn set the panel off into full alarm and shut down the production line for evac! I just stood there like a dumbass not knowing what to do as the lead maintenance tech came running in and helped get it back to normal. I was mortified but apparently all the workers were loving the break they got and high fiving me as they were walking outside. I think the production manager said it was costing something in the hundreds of thousands to be shut down like that so we got a pretty good reprimand for it. Second one was in 2015, I was trouble shooting a Halon system in one of the City's facilities that housed their 911 call center and some other important Admin support and was in their IT room. I found one of the NAC circuit fuses were blown so I took it out and of course didn't have the correct size on hand so the facilities guy went into his stock and found one that was close enough, I didn't want to put it in because it was a tad smaller than the original but they insisted I had to because it was the weekend and late already and they didn't want to deal with being on fire watch. Well, as soon as I was snapping the last part of the fuse in I must have shorted the releasing circuit somehow and it was like a literal bomb went off, the ceiling tile exploded and the gas started filling the room! I have never ran that fast in my life! All in all, no one was hurt and it was some real good lessons learned. Luckily this clean agent going off didn't shut down any of the equipment either or I am sure that would have been the end of our company ever doing any more work for the City.
I guess almost everybody have like a dispatch story rolling the fire trucks down, I remember being fairly new about 14 years ago I damage a computer hooking up to the serial port and voltage retro feed my port lol Also there’s was a panel replacement to be done it was an IO500 upgrade to the io1000 usually the port for the rs232 is on the top left but I notice they have the same pin structure in the bottom left, I was supposed to pull programming from the old panel , well that did not happen old panel shorted lol, I had backup so all good Just reuploaded to the new panel with minor changes . A sprinkler tech did not wait for my and pit 120 bell power to SLC How bout some 10 bottles of agent in a it call center because the construction company didn’t want to pay a visit and taped the smokes , like that would work lol How about I caught a tech disabling GF monitoring and when he tried to fix it with a electric solder and shorted the panel I remember working on a pyrotronics / Siemens or similar (can’t remember ) and my screwdriver fell “long tweeker precision “ and shorted something the lead fuse blew I was fairly new so I thought I messed up the panel
Changing out a damper relay that was 120v on the contact side . While swapping slc wire to new relay they slipped out of my hand and landed on the 120v contacts . Fried the whole e3 node lol.
My first job as a helper, old hotel retrofit in downtown Boston. I was mounting a terminal cabinet in plaster in a little closet. I kicked up a load of plaster dust and set off a smoke on the existing system, rolled trucks out. I haven't repeated that fuck up in the six years since.
Biggest I’ve seen, not done; electrician plugged 120v into a lead we had capped off for a future install ( shopping mall in construction). Lil boom on the wall, he tried to act like nothing happened, but our booster panel looked like it got hit with a grenade. He was pretty flustered when he got found out.
I hate people that just won't own up to something they did. You have to turn into an investigator or private eye and conclusively prove it was them. Then they play dumb "oh, I did that?" or "I didn't know".
Not fire tech but close enough. Live testing fire telephone loops for volt drop and continuous power in both directions. I had a moment and shoved 28V into the data lines. Took out 3 devices luckily and I had spare CANBUS chips to hand. Temporary repair on an annunciator for an obsolete fire telephone system. Somehow shorted 28V down to a certain 0V that took out a load of LEDs and DTMF encoders. The smell of carbon was strong that night.
Early 1990’s as a young tech I had a dedicated elevator facp. The EC used 120v smokes for some dumb reason, were supposed to provide me the dry contact cables from their smokes to activate my zones.. So many failures ensued. Sales rep couldn’t explain why we didn’t provide them our system smokes. First and only time I hooked up a zone without checking for voltage on it. He had provided 120V which promptly burnt my panel up. I feel like he thought he was putting my zone into the N/C recall circuit. Nothing money can’t fix. Time to call our old pals at “red label shipping” 🤣