The website description lists the lineup of Midnite Solar Surge Protective Devices as a Type 1 device.
The installation manual denotes the device as Type 2.
Wonder if the disagreement has anything to do with older model may have been Type 1 ?
This says they are all Type 2
http://www.midnitesolar.com/doc_prod_list.php?menuItem=products&productCat_ID=23&productCatName=Surge%20Protection%20Devices
The ones I have all say Type 2 on them .
Larry
Yeah, that shifts the preponderance of evidence toward Type 2.
I was just trying to figure out how they work. I mean the Midnite units specifically. I read through the PDFs, including Robin's nice write up. He only mentions metal oxide varistors though. I understand how those work. But is there more going inside that glass cage or are the MOVS the core? I've seen references to 'air gap' for surge protection.
Wait. I just googled the difference between type 1 and type 2. Found a UL related document here:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwjF5dXHp4rVAhWr34MKHQuPCKkQFgh2MAE&url=http%3A%2F%2Fwww.electrical-installation.org%2Fenwiki%2FThe_Surge_Protection_Device_(SPD)&usg=AFQjCNFeBcPf7hzNP_mpSJO1rWhPxdtRqQ
It appears type 2 devices are more restricted in their placement. Moreover, it seems type 2 devices may or may not include "external overcurrent
protection". It is not required. Which leads to the next question: Do the Midnite devices incluse such protection, and if not, why not? (I sure ask a lot of questions, don't I?)
----------------------------------------------
EXCERPT FROM PAPER:
Some key differences between Type 1 and Type 2 SPDs are:
External Overcurrent Protection. Type 2 SPDs may require external overcurrent
protection or it may be included within the SPD. Type 1 SPDs generally include
overcurrent protection within the SPD or other means to satisfy the requirements
of the standard; thus, Type 1 SPDs and Type 2 SPDs that do not require external
overcurrent protection devices eliminate the potential for installing an incorrectly
rated (mismatched) overcurrent protection device with the SPD.
Originally the MidNite SPDs were Type 1 rated. All type 1 means is that you can legally connect them up
to the utility side of the breaker box. That doesn't make them any better, really.
This was because ETL assumed some things that they later had to change.
The MOVs have internal over-current protection but not proper for that specification.
Because of this, the newer SPDs have separate over-current protection in addition to the MOVs
and they have been re-tested. That was fun going to Boston at a facility with 1000V and
100,000 amp capability. We only needed 10,000 amp capability. Those tests were not
for lightning but were for abnormal overload like, if a tree falls on your house and your
120/240 VAC lines turn into a constant 480 VAC source.
There is a newer SPD spec that we also comply with but I can't remember what that
type or spec is called right now.
Just all part of the game we have to play with the NRTLs. It's all good.
boB
I suspected that the devices had been reclassified from 1 to 2 and that the paperwork hadn't caught up yet. Doesn't see to be a problem given where they are
being installed.
thanx for the clarification.