Internal vs. External Mounted Surge Protection

The big question is what type of TVSS is best for your facility, Internally mounted integral units sold by the switchgear manufacturer or an Externally mounted unit sold separately.

Switchgear manufacturers will boast integral units take away installation issues such as lead length (should be less than 6") and sharp bends. Although true, and important, that is but a small piece of a much larger puzzle when deciding on the proper TVSS for your application. It is also worth noting that TVSS should never be purchased if the manufacturer can not provide IEEE performance data.

The truth is, when engineering a new application or protecting an existing facility the time and convenience you save initially, may come back to haunt you later.

It is becoming common knowledge that all facilities will benefit by installing quality, Transient Voltage Surge Suppression (TVSS).


	Issues to consider with Internal or Integral Mount TVSS
	Switchgear must be powered down by the Utility when replacing failed unit.
	Power to facility may be interrupted during replacement period.
	Replacement can only be done by authorized factory personnel during warranty period.
	Failed units may cause collateral damage to surrounding switchgear and out gassing can be an issue.
	Higher risk of arc flash/blast hazard.
	Most units have a limited 5 to 10 year warranty with limited performance data.
	Enhanced Transient Filter or Sine Wave Tracking is usually not offered to protect sensitive electronic equipment.


	Benefits of External Mount Panel TVSS Units
	The easy installation of a breaker for a means of disconnect is usually all that is needed to avoid powering down the panel.
	Replacement of unit does not require powering down the panel and can be done by qualified facility personnel even during the 30 Yr. Free Replacement Period.
	Catastrophic damage to other equipment is eliminated due to the heavy gauge Steel, NEMA 4 enclosure.
	The TPS unit is internally fused, both for thermal and overcurrent, therefore they fail safely regardless of whether the failure is caused by lightning or a temporary or sustained over voltage condition.
	The use of an externally mounted unit will limit the arc flash/blast exposure.
	30 Year Free Replacement Warranty....Unconditional!
	Optional, Enhanced Transient Filter to protect all electronic devices including PLC's, High Efficiency Lighting, POS, and Computers.

In Summary

When it comes to Surge Suppression, for personnel safety, power quality and lightning protection, TPS, external panel mount units with an Enhanced Transient Filter will protect your facility's critical equipment better than the integral units made by switchgear manufacturers. If you want the best Warranty, fastest Return on Investment, units that meet their published per mode strength and will reduce glitches, lock-ups and failures due to transients, then your best choice is a Surge Suppressor by:

Other Transient Times news articles:

Flourescent Bulbs are Energy Efficient, not Maintenance Efficient

Toronto Transformer Fire Causes Province-wide Voltage Dip

Power Surges Can Fry Your Sensitive Electronics
Toronto Hydro Recommends Surge Protection Equipment

When Do You Need Transient Voltage Surge Suppression (TVSS)?