We have an existing access control customer that expanded into a new building. We were brought in from the start to assist in the planning and code compliances for access control. No biggie, just some public areas, stairs, elevators, fire alarm integration, (us), and CCTV (also us).
From the beginning, we were told the front doors were going to be double doors with one stationary non electrified crashbar and one access controlled electrified crashbar. From the start, the electricians were to provide conduit to the electrified door from the crashbar's power supply which was over 50 feet away. There was also to be a removable center mullion. This sounded feasible but I was uneasy about the second non-electrified crashbar and the fact the doors would be quite a distance away from the power supply. The customer was warned on numerous occasions during our weekly construction meetings this would be a one time decision once installed because the doors were surrounded by glass and wood trim which could not be removed if they changed their minds. The customer was adamant that the front door configuration was passed by their board and the AHJ and would never change.
The electricians moved the power supply box even further away so we had to increase the wire gauge size again to accommodate the voltage drop. This maxed out the already run 1/2 conduit fill to the door because the 12 conductor access control cable was in the same conduit. Again, no changes to the front doors.
The glazers did their job followed by the finish carpenters and their expensive wood trim, glued and nailed. All of our wiring was pulled to the power supply for the control and to the door reader, contacts, REX motion, and down the jamb for the transfer hinge.
True to form, the change order came down to change both doors to electrified vertical rods with crashbars. Having no extra cables from the power supply to the added door, we dutifully ran a 12 gauge pair for a power jumper from the electrified door to the added door. See rule #1 in customer service, something about them always being right.
Of course the problems we had warned our customer about began. The doors would not open and stay open upon input either controlled by time zone or card read. I explained the causation and even demonstrated their initial single door setup would work by disconnecting the second door. After weeks of back and forth finger pointing and multiple service calls trying even the door contact wires for the additional power I was fed up.
On the last service call we were going to perform I had an epiphany. I watched the doors try to work then both solenoids quit holding after a few seconds. I disconnected the first door and the second one unlocked! I added the first door to the circuit and it too unlocked and stayed unlocked! I had to delay the second door power to unlock after the first door! I proved this by manually making the connection to the second door after the first unlocked and leaving for the day then returning to check my theory. I added an IDEC GT3 series 24 VDC DPDT timer relay which delayed the second door unlock by 3 seconds. http://us.idec.com/Catalog/ProductSeries.aspx?SeriesName=GT3A_Series&FamilyName=Timers This let the power supply open both front doors and keep them open all day. The bonus was the relay fit inside the second crashbar not interfering with the mechanism. This fix has worked for over two years with no problems
My take away on this experience is always plan for the change order even if they swear on a Bible there will never be one. A few extra dollars would have made us heros without all of the grief both of us experienced.
From the beginning, we were told the front doors were going to be double doors with one stationary non electrified crashbar and one access controlled electrified crashbar. From the start, the electricians were to provide conduit to the electrified door from the crashbar's power supply which was over 50 feet away. There was also to be a removable center mullion. This sounded feasible but I was uneasy about the second non-electrified crashbar and the fact the doors would be quite a distance away from the power supply. The customer was warned on numerous occasions during our weekly construction meetings this would be a one time decision once installed because the doors were surrounded by glass and wood trim which could not be removed if they changed their minds. The customer was adamant that the front door configuration was passed by their board and the AHJ and would never change.
The electricians moved the power supply box even further away so we had to increase the wire gauge size again to accommodate the voltage drop. This maxed out the already run 1/2 conduit fill to the door because the 12 conductor access control cable was in the same conduit. Again, no changes to the front doors.
The glazers did their job followed by the finish carpenters and their expensive wood trim, glued and nailed. All of our wiring was pulled to the power supply for the control and to the door reader, contacts, REX motion, and down the jamb for the transfer hinge.
True to form, the change order came down to change both doors to electrified vertical rods with crashbars. Having no extra cables from the power supply to the added door, we dutifully ran a 12 gauge pair for a power jumper from the electrified door to the added door. See rule #1 in customer service, something about them always being right.
Of course the problems we had warned our customer about began. The doors would not open and stay open upon input either controlled by time zone or card read. I explained the causation and even demonstrated their initial single door setup would work by disconnecting the second door. After weeks of back and forth finger pointing and multiple service calls trying even the door contact wires for the additional power I was fed up.
On the last service call we were going to perform I had an epiphany. I watched the doors try to work then both solenoids quit holding after a few seconds. I disconnected the first door and the second one unlocked! I added the first door to the circuit and it too unlocked and stayed unlocked! I had to delay the second door power to unlock after the first door! I proved this by manually making the connection to the second door after the first unlocked and leaving for the day then returning to check my theory. I added an IDEC GT3 series 24 VDC DPDT timer relay which delayed the second door unlock by 3 seconds. http://us.idec.com/Catalog/ProductSeries.aspx?SeriesName=GT3A_Series&FamilyName=Timers This let the power supply open both front doors and keep them open all day. The bonus was the relay fit inside the second crashbar not interfering with the mechanism. This fix has worked for over two years with no problems
My take away on this experience is always plan for the change order even if they swear on a Bible there will never be one. A few extra dollars would have made us heros without all of the grief both of us experienced.
