[RE-wrenches] DC conductor line loss numbers

[jerrysgarage01]

Wrenchesthe VD is 105 VDC into  a charge controller, the engineer is looking good at it like it a grid tie running at wide open all the time, he will not listen to sugestions, that's the problem I haveJerry


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-------- Original message --------
From: Jarmo.Venalainen at schneider-electric.com 
Date: 07/27/2015  5:34 AM  (GMT-10:00) 
To: RE-wrenches <re-wrenches at lists.re-wrenches.org> 
Subject: Re: [RE-wrenches] DC conductor line loss numbers 

Hi:



When deciding on voltage drops and otherwise
working out the design of a solar system, one thing that needs careful
attention is to make sure that the array voltage does not drop below a
level at which the inverter cannot produce full power.



This voltage will occur when the inverter
is working at full input current such as a hypothetical 3000 W inverter
which can handle a maximum of 10 Amps of input current to produce its full
rated 3000 Watts (10Amps @ 300 Vdc).  



At any voltage less than 300 Vdc, the
power will be limited by the maximum 10 Amps.  For example at 290
Vdc you get 2.9 kW, 280 Vdc you get 2.8kW, and so on.



Even if the inverter can operate
down to 100 Vdc, you don't want to be anywhere near there, especially not
during the midday hours as that will hurt peak power production, a lot.
 In this case -0.3% loss for every volt below 300Vdc.









Identifying this voltage for a particular
inverter may not however be straightforward due to wide variety of wording
used in specifying ratings.  Wording such as,



1. operating voltage range

2. full power operating voltage range

3. MPPT operating voltage range

4. minimum operating voltage

5. minimum MPPT operating voltage

6. rated operating voltage range

7. Rated MPPT operating voltage range

8. starting voltage

9. nominal operating voltage range

10. maximum input current

11. minimum input voltage

12. minimum DC voltage

13. nominal DC input current

14. maximum operating DC input current

15. maximum continuous operating DC
input current

17.........





When looking for the voltage below which
you don't want go, look for the following:



1. The maximum operating input current

2. The minimum MPPT operating voltage



Then make sure the array can produce
at least that much voltage and current when its really hot when the resistance
of all the wires is more than at room temperature.



JARMO

_____________________________________________________________________________________




Jarmo Venalainen  |  
Schneider Electric   |  Xantrex
Brand  |   CANADA  |   Sales Application
Engineer 

Phone: +604-422-2528  |   Tech Support: 800-670-0707
 |   Mobile: +604-505-0291 

Email: jarmo.venalainen at schneider-electric.com
 |   Site:
www.Xantrex.com  |  
Address: 3700 Gilmore Way, Burnaby, BC V5G4M1 















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From:
Glenn Burt <glenn.burt at glbcc.com>

To:
RE-wrenches <re-wrenches at lists.re-wrenches.org>,


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