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Chele
join:2003-07-23

Chele to John Galt6

Member

to John Galt6

Re: OT - Site Monitoring Device - Input Needed

said by John Galt6:

said by voxframe:

The I/O will accept industry-standard 4-20mA and 0-10V.

Make it able to handle up to 36v so that it can be connected directly to solar power systems. We have had to use voltage regulators only because UBNT won't work on anything above 24-25v, my gripe with that is not the cost of the voltage regulator but it's just one more piece that can fail. Let the units have dual input sensors--one to measure the solar feed and another to measure battery condition. I know it's going above and beyond your initial intentions, buuuuuut-----------make a unit with remote rebooting/ping watchdog capabilities. It goes without saying, make it rugged! It's amazing the working conditions we subject the equipment to and ask(demand!!) that they work reliably. As always, pricing is an issue--most WISPs will have several POPs and it begins to add up.

John Galt6
Forward, March
Premium Member
join:2004-09-30
Happy Camp

John Galt6

Premium Member

said by Chele:

Make it able to handle up to 36v so that it can be connected directly to solar power systems.

Units will accept up to 48V at either the power connector or POE.

Let the units have dual input sensors--one to measure the solar feed and another to measure battery condition.

Gots!

I know it's going above and beyond your initial intentions, buuuuuut-----------make a unit with remote rebooting/ping watchdog capabilities.

Done.

It goes without saying, make it rugged! It's amazing the working conditions we subject the equipment to and ask(demand!!) that they work reliably.

Various cases are an option for demanding conditions (IP65 and such).

As always, pricing is an issue--most WISPs will have several POPs and it begins to add up.

But of course! That is the whole objective here...to reduce the cost of such technologies significantly.
Chele
join:2003-07-23

Chele

Member

Well, never mind, if you're going to be difficult about it Put me down on your list, it sounds promising!
bburley
join:2010-04-30
Cold Lake, AB

bburley to John Galt6

Member

to John Galt6
said by John Galt6:

said by Chele:

Make it able to handle up to 36v so that it can be connected directly to solar power systems.

Units will accept up to 48V at either the power connector or POE.

48V is not enough for 48V Solar systems. Our 48V battery bank can reach 64V during peak charging. I blew up two $700 boards that were rated at 70V due to the "stiff" supply voltage at the instant of turn-on. Finally had to install a 24V DC-DC Converter and run from that. Funny that the converter was also rated at 70V input but it survives. It was cheaper than blowing up another board.

John Galt6
Forward, March
Premium Member
join:2004-09-30
Happy Camp

John Galt6

Premium Member

said by bburley:

said by John Galt6:

said by Chele:

Make it able to handle up to 36v so that it can be connected directly to solar power systems.

Units will accept up to 48V at either the power connector or POE.

48V is not enough for 48V Solar systems. Our 48V battery bank can reach 64V during peak charging. I blew up two $700 boards that were rated at 70V due to the "stiff" supply voltage at the instant of turn-on. Finally had to install a 24V DC-DC Converter and run from that. Funny that the converter was also rated at 70V input but it survives. It was cheaper than blowing up another board.

Talking with the interface engineer...he says that it can accept line voltage, properly protected (fused and current-limited).

Our objective is to limit the on-board working voltages to 50 volts or less, as this is the breakpoint for Class 2 devices. The requirements are far less stringent in many applications.

A voltage divider prior to the input is easy to do...more than happy to sell you one for $99.
bburley
join:2010-04-30
Cold Lake, AB

bburley

Member

A voltage divider is usually just two resistors which is only suited for steady current loads, unless you meant something else.

The DC-DC Converter worked out well. Everything but the touchy board was running on 48V. Having 24V available allowed me to add a MikroTik Router later on.

The touchy board had an on-board regulator which allowed it to work with an input voltage as low as 15V or so. It was the regulator that kept exploding at turn-on.