Markc
-
It's worth an email I think
-
Please use style selector to select BLUE AND WHITE. If you are not already on it. This notice will go once you're on the correct style.
Markc
-
Well I had a very interesting telephone conversation from a tech guy at Kraus Naimer about removing links in the DC isolator and as you might well of guessed it isn't black and white! I hope he will stand by his word and email me what we discussed so I can post on here but until then I hope this may help (a little) but please this is not 100% and don't take my word for it.
Their range of DC isolators is divided into 4, 6 and 8 pole devices. 4 pole rated to 200V, 6 pole to 600V and 8 pole to 800V. He recommends never removing links from the 4 or 6 pole isolators (T104, T106) but when it comes to the 8 pole (T108) he said it may be possible to remove only two links (one each pole) to render them 4 pole BUT it reduces the voltage to 400V. So if the array string is less than 400V it is possible to use one DC isolator for two strings. It also reduces the contact amperage considerably. He did say that considering the cost of a DC isolator he found it puzzling why someone would prefer to do this?
Like I say please don't consider this as a statement of fact merely as passing on a telephone conversation. Your job your risk!
Their range of DC isolators is divided into 4, 6 and 8 pole devices. 4 pole rated to 200V, 6 pole to 600V and 8 pole to 800V. He recommends never removing links from the 4 or 6 pole isolators (T104, T106) but when it comes to the 8 pole (T108) he said it may be possible to remove only two links (one each pole) to render them 4 pole BUT it reduces the voltage to 400V. So if the array string is less than 400V it is possible to use one DC isolator for two strings. It also reduces the contact amperage considerably. He did say that considering the cost of a DC isolator he found it puzzling why someone would prefer to do this?
Like I say please don't consider this as a statement of fact merely as passing on a telephone conversation. Your job your risk!
J
JulianC
Interesting stuff. Makes sense.
Errr, because his rep was telling people they could perhaps?!
Errr, because his rep was telling people they could perhaps?!
Markc
-
Interesting stuff. Makes sense.
Errr, because his rep was telling people they could perhaps?!
I did make that point Julian. If you can get a shrug of the shoulders on the phone that's what I got!
Markc
-
Had a email form K&N today. See below and PDF's:
Hello Mark,
Please find attached data sheets which show the amended connections required to use our T104, T106 & T108 disconnect switches for isolation of two PV strings. Rating data for the two string operation is also included.
The following points should be noted with regard to implementing these changes.
Please call if you would like to discuss any points.
Kind regards,
Denis
Denis Thomas
Technical Sales Manager
Hello Mark,
Please find attached data sheets which show the amended connections required to use our T104, T106 & T108 disconnect switches for isolation of two PV strings. Rating data for the two string operation is also included.
The following points should be noted with regard to implementing these changes.
- As there will be twice the number of cables to be accommodated in the enclosure, it is important to ensure that the enclosure has sufficient cable entry holes and that the cables being used can be accommodated in the enclosure.
- Cable entry is often necessary via both the top and bottom entries in the enclosure.
- The rating date provided is based on selecting by DC-21B utilization category in order to maximize the current rating at each listed voltage. The potential disadvantage is a reduced number of switching operations, but in view of the application, this is most unlikely to represent any problem and most of our competitors use DC-21A or B as the selection criteria for their PV switch-disconnectors.
Please call if you would like to discuss any points.
Kind regards,
Denis
Denis Thomas
Technical Sales Manager
OFFICIAL SPONSORS
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc
YOUR Unread Posts
-
-
RCD mainswitch? What's the best way forward?- Latest: Jock from the north
-
