SEPTA Gate System

OVERVIEW

Sensitive electrical equipment, such as turnstiles and automated gates, rely on surge protection devices (SPDs) to prevent damage from sudden voltage spikes caused by lightning, power grid fluctuations, or electrical switching events. These access control systems are critical for security, ensuring controlled entry and smooth operations in facilities like airports, stadiums, corporate offices, and transit hubs. A power surge can cause system failures, leading to security vulnerabilities, operational disruptions, and costly downtime. The Insurance Institute for Business & Home Safety study found that $26 billion dollars was lost due to non-lightning power surges. In addition, there are about 25 million lightning strikes in the US each year that cause between $650M to $1B in losses according to the Insurance Information Institute, State Farm©.

Selecting SPD for Turnstiles and Gates

NEC/NFPA 70 requires that Surge Protective Devices (SPDs) shall be UL1449 Listed. This means selecting a surge protector is easier than it has ever been. There are only a few choices available for SPDs that are UL Listed for any of the most commonly used surge standards including UL1449 5th Edition, UL497B, and UL497E.

Outdoor Full-height gates and Turnstiles	Waist high turnstile	Waist high Optical Turnstiles	Barrier Optical Turnstiles

Recommended SPD for Outdoor/Indoor Turnstiles & Gates

Location	Equipment	System	Surge Protector Model#	Link
Service Entrance	Main Service Panelboard	277/480Vac	MDS750E-277Y
Branch Panel	Equipment Panelboard	480Vac	M50-480D-A
Local Equipment	Control Panel	480Vac Power Input	DS74US-480D
	Power Supply	120-240Vac Power Input	DS72US-230S/G
		24Vdc Power Output	DS220S-24DC
	Control Unit	Ethernet Cat 6A	MJ8-C6A
		4-20mA	DLA-24D3

The UL inspector will first consider the SPD type when determining it’s acceptability for a given application or piece of equipment. This will include UL 508A as well as all other UL Listed equipment. The first level compliance is based on the UL Approval (LISTED or RECOGNIZED) of the SPD or UL SPD Type and it’s Suitable Ratings. This means that it has to meet all safety, performance, environmental and electrical system ratings of the application. If any of these criteria are not fully met, it will require a Procedure Description, a File Update and/or Additional Testing. These actions will require additional costs that may be substantial. For this reason, it is in the interest of the specifier to use UL LISTED SPD’s to eliminate any uncertainty or to make sure the UL RECOGNIZED SPD is selected at the time of UL submittal of the equipment.

Approval Considerations Table based on UL SPD Type

UL Mark	UL1449 SPD Type	Suitable Ratings	Procedure Described	File Update or Additional Testing	Notes
	1 2	Yes	No	No	The only requirement is that the SPD must match electrical and environmental ratings of the UL 508A Control Panel. A UL field inspection of the control panel with the SPD installed is required as a part of a standard follow-up service visit.
	1CA 2CA 4CA 5	Yes	Yes	Yes	Yes – All UL recognized SPD’s require a UL engineering evaluation of the SPD’s existing UL1449 E–file. This will result, at a minimum, in a cost to update the UL file and may also require testing that would result in additional costs.

References