Looking for DC voltage, amperage, wattage, kw meter?

jimmyaz

Hey guys,

I am currently using this meter for my offgrid and it work great.

https://www.amazon.com/bayite-6-5-100V-Display-Multimeter-Voltmeter/dp/B013PKYILS/ref=sr_1_1?ie=UTF8&qid=1481565146&sr=8-1&keywords=bayite+dc+meter

It measure DC voltage, amperage and wattage and accumulated energy and displayed them all and I love it.

However, my new project required DC voltage is 160volts, but this little meter max out at 100V DC.  I have been looking all over the place, but can not find any alternative with a decent price... (less then 50.00).  This company made the same product that can do up to 260volts, but for AC only.

The only other one I found that reasonable is this one.
https://www.amazon.com/gp/product/B015PQ7L5K/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=AFHAE9RJVUMB

But it only show voltage and amps.... not watts or most important, accumulated power.



Any ideas?

thanks

BB.

Depending on how the meter is wired--Using a resistor divider on the voltage input may work. Scale by 1/2 to 1/10 -- The voltage will be "wrong" and so will be the power--But you only have to multiply by your scaling factor to get it right for logging.

-Bill

jimmyaz

Hey guys,

If I have 4 panels, put 2 in series then parralles the set together... Do you guys think I should install bypass diodes between the two parallels set?

Let say one set may get some shadow over it at certain time (neighbor tree)

mike95490

jimmyaz said:

Hey guys,

If I have 4 panels, put 2 in series then parralles the set together... Do you guys think I should install bypass diodes between the two parallels set?   ......

No. 

  Who is that person planting ideas that you have to have a bunch of diodes to have solar work ??

jimmyaz

mike95490 said:

jimmyaz said:

Hey guys,

If I have 4 panels, put 2 in series then parralles the set together... Do you guys think I should install bypass diodes between the two parallels set?   ......

No. 

  Who is that person planting ideas that you have to have a bunch of diodes to have solar work ??

https://www.youtube.com/watch?v=5rYy0gHZepI

Saw this video.. not 100% sure if it's true.  3:20 is where she start talking about two panels in parallels and one being shaded. 

mcgivor

mike95490 said:

jimmyaz said:

Hey guys,

If I have 4 panels, put 2 in series then parralles the set together... Do you guys think I should install bypass diodes between the two parallels set?   ......

No. 

  Who is that person planting ideas that you have to have a bunch of diodes to have solar work ??

As most, if not all modern PV panels already have bypass diodes installed in the junction box to bypass shaded cell strings within the panel, the only additional diodes you could install would be panel bypass or blocking.

A panel bypass would essentially eliminate the entire panel, so instead of getting say 66% power, if 2 cell strings within the panel were bypassed, for example, you would get nothing.

Blocking diodes prevent back feed from the battery to the panels when they are producing nothing, but are unnecessary as the charge controller already has diodes to prevent this.

The parallel panel question, one shaded on a sailboat for example, would addressed by using 2 separate controllers, so by her own admission, diodes are not the best method.

So unless I am missing something @mike95490 is correct, No they are not needed.