glaughlen
New User
- Location
- brooksville, fl. usa
First time poster, Not sure if this is the correct place to post my question but here goes:
I am trying find out if there is a code addressing back feed prevention for a generator docking station?
The problem being there is an existing docking station(aka DS) installed as part of a manual transfer switch application with kirk keys between the DS breaker and the main breaker. In this configuration there is a permanent generator connected directly to the bus associated with the quick connectors and the load is isolated by the internal breaker(Normally open) preventing utility from back feeding quick connects and genset. The instructions for operation are clear “Open main breaker, remove kirk key, manually start genset, insert kirk key in DS and close the DS breaker”
The engineers new design for adding an Automatic transfer switch to the system is leaving the DS connected to the genset as is and connecting the output of the DS to the “E” side input of the ATS. The DS breaker will now be “Normally closed”.
My concern is the quick connects can become lethally energized if the genset is commanded to start by the ATS
The scenario is a tech on site to connect a load bank and approaching the DS and opening the breaker expecting the quick connects to be safe and if the tech were to meter the quick connects they would be de-energized at this point begin connecting cables. If the ATS should happen to command the genset to start the quick connects would become lethally energized(277/480v) within say 8-10 seconds without any notification.
I have pitched my concern to the AHJ and they currently agree with my concern but the customer and the engineer do not agree with my concern and feel a placard or signage is sufficient to protect personnel from harm.
My question is there a code addressing this type of safety issue?
Proposed new design, PD-0012 will be “Normally closed” not “Normally open” as shown.
Example of the correct design
I am trying find out if there is a code addressing back feed prevention for a generator docking station?
The problem being there is an existing docking station(aka DS) installed as part of a manual transfer switch application with kirk keys between the DS breaker and the main breaker. In this configuration there is a permanent generator connected directly to the bus associated with the quick connectors and the load is isolated by the internal breaker(Normally open) preventing utility from back feeding quick connects and genset. The instructions for operation are clear “Open main breaker, remove kirk key, manually start genset, insert kirk key in DS and close the DS breaker”
The engineers new design for adding an Automatic transfer switch to the system is leaving the DS connected to the genset as is and connecting the output of the DS to the “E” side input of the ATS. The DS breaker will now be “Normally closed”.
My concern is the quick connects can become lethally energized if the genset is commanded to start by the ATS
The scenario is a tech on site to connect a load bank and approaching the DS and opening the breaker expecting the quick connects to be safe and if the tech were to meter the quick connects they would be de-energized at this point begin connecting cables. If the ATS should happen to command the genset to start the quick connects would become lethally energized(277/480v) within say 8-10 seconds without any notification.
I have pitched my concern to the AHJ and they currently agree with my concern but the customer and the engineer do not agree with my concern and feel a placard or signage is sufficient to protect personnel from harm.
My question is there a code addressing this type of safety issue?
Proposed new design, PD-0012 will be “Normally closed” not “Normally open” as shown.
Example of the correct design