Intermatic Whole House SPD

[mikeames]

Maybe this has been out for a while but I just came across it and like the replaceable modules. I always had issue with the fact the SPD had to be replaced due to the sacrificial nature, but I still installed them in my house. Now this. I am thinking of getting this for my own house. Anybody have experience with this one? My only concern is the length of the conductors to feed this impact performance, or is that minimal. I thought the length of the conductors need to be as short as possible.

Also, I heard the term TVSS is no longer used, or replaced, why?

https://www.intermatic.com/en/surge-protection/whole-house-surge/ig2240-imsk

 

[Beaches EE]

Lead length should be as short as practically possible because transient current rise (di/dt) is high and lead inductance can hinder the effectiveness of the device. UL recently changed the terminology from TVSS to SPD, not sure why though.

 

[Jraef]

Replaceable modules have been around for years in industrial SPDs, but for the most part residential users are not subject as often to the level of surges that take them out, so people have not been willing to spend the extra money to get that feature. Maybe that has changed...

The change actually happened way back in 2009, but it has taken a long time to get it through to everyone. TECHNICALLY, the term "TVSS" only applied to devices DOWNSTREAM of a main service OCPD, whereas an SPD was defined as protecting the UTILITY and, in industrial / commercial installations, the SWITCHGEAR side of equipment. TVSS had tighter voltage "clamping" specs for sensitive devices on the load side of the service, but were capable of less total energy than SPDs. The use of two different terms based on the location was getting muddied by importers making claims, one way or the other, and being wrong, per the ANSI/UL 1449 specifications. So ANSI/UL changed the terminology, making them all "SPDs", then creating 5 different "Types" based on where in the circuit they were to be used.

[*]Type 1– A permanently connected SPD intended for installation between the secondary of the service transformer and the line side of the service equipment overcurrent device, as well as the load side, including watt-hour meter socket enclosures and Molded Case SPDs intended to be installed without an external overcurrent protective device.
[*]Type 2– A permanently connected SPD intended for installation on the load side of the service equipment overcurrent device, including SPDs located at the branch panel and Molded Case SPDs.
[*]Type 3– Point of utilization SPDs, installed at a minimum conductor length of 10 meters (30 feet) from the electrical service panel to the point of utilization, for example cord connected, direct plug-in, receptacle type SPDs installed at the utilization equipment being protected. The distance (10 meters) is exclusive of the conductors provided with or used to attach SPDs.
[*]Type 4– Component Assemblies -,Component assembly consisting of one or more Type 5 components together with a disconnect (internal or external) or a means of complying with the limited current tests.
[*]Type 1, 2, 3 Component Assemblies – Consist of a Type 4 component assembly with internal or external short circuit protection.
[*]Type 5 – Discrete component surge suppressors, such as MOVs that may be mounted on a PWB, connected by its leads or provided within an enclosure with mounting means and wring terminations.

At the same time, the issue of SCCR of the devices was added, so that you would know whether or not the SPD was suitable for connection at your equipment. So by eliminating TVSS as an official term, you could immediately identify a vendor selling you something that may not be properly listed for the application.

 

[mikeames]

Replaceable modules have been around for years in industrial SPDs, but for the most part residential users are not subject as often to the level of surges that take them out, so people have not been willing to spend the extra money to get that feature. Maybe that has changed...

The change actually happened way back in 2009, but it has taken a long time to get it through to everyone. TECHNICALLY, the term "TVSS" only applied to devices DOWNSTREAM of a main service OCPD, whereas an SPD was defined as protecting the UTILITY and, in industrial / commercial installations, the SWITCHGEAR side of equipment. TVSS had tighter voltage "clamping" specs for sensitive devices on the load side of the service, but were capable of less total energy than SPDs. The use of two different terms based on the location was getting muddied by importers making claims, one way or the other, and being wrong, per the ANSI/UL 1449 specifications. So ANSI/UL changed the terminology, making them all "SPDs", then creating 5 different "Types" based on where in the circuit they were to be used.

At the same time, the issue of SCCR of the devices was added, so that you would know whether or not the SPD was suitable for connection at your equipment. So by eliminating TVSS as an official term, you could immediately identify a vendor selling you something that may not be properly listed for the application.

That's great info. Thanks