Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
No mention at all of being a schottky diode. I think this may just be a standard silicon diode. No Vf vs. I plots, either. I think there are better options available.
It is a silicon diode.
From the datasheet Vfm = 1.4 volt. No mention of the If or Tc conditions where Vf was measured, which would significantly change that voltage value.
My original problem was something else but using a diode here is also solving my another problem with the ups.
My ups/inverter has a low battery cut off voltage of 10.4v, which i think is pretty damn low for a 12.0v battery.
So by using a diode here between the charging cable and battery terminal, and using a diode's voltage drop, i think i can make my ups think that it is disconnecting the battery at 10.4 but in reality it will be cutting off at 11.1v if the voltage drop of diode is 0.7v.
Did you get what i am trying to do here?
10.4v + 0.7 = 11.1v, so when battery voltage reaches 11.1v ups would think it is 10.4v and will disconnect the battery.
I have a small solar panal which efficiently charges the battery so i don't need the charger inside ups.
So is there such a stud diode with 0.7 or less voltage drop with current capability for handling about 30 to 40Amps or even 50?
Don't worry about heat sink... I think i can manage it.. but voltage drop shouldn't be more than 0.7 under any condition.
Have you considered an ideal diode. There are 2 types - one based on a PFET and one on an NFET. At that sort of power, an NFET would be a far superior solution. LTC do NFET ideal diode controllers and you can (to a certain extent) pass as much current as you like
Have you considered an ideal diode. There are 2 types - one based on a PFET and one on an NFET. At that sort of power, an NFET would be a far superior solution. LTC do NFET ideal diode controllers and you can (to a certain extent) pass as much current as you like
Have you consider locating the nefarious 10.4 V comparator in your UPS and adjust the resistor ratios to get 11.1V and cutoff. Significantly easier to change...
Have you consider locating the nefarious 10.4 V comparator in your UPS and adjust the resistor ratios to get 11.1V and cutoff. Significantly easier to change...
then learn to be qualified... get a meter and look for an LM3xx chip to switch voltages on the output pins of the datasheet , when battery runs out, measure the input voltages on same IC, power down look for connected R's , take pictures , ask questions.
then learn to be qualified... get a meter and look for an LM3xx chip to switch voltages on the output pins of the datasheet , when battery runs out, measure the input voltages on same IC, power down look for connected R's , take pictures , ask questions.
If it's a relay cutoff, you can trace back from the coil to the driver transistor which will probably be fed by the comparator I.C. (8pin?) doing the voltage trip. If the relay driver is NPN or N channel then the comparator output swings high to trip. Vice versa for a PNP or P channel Relay coil driver.
It's possible but unlikely that they used a couple transistors biased to do the tripping.
If they used an ADC voltage sampling microcontroller , well, it gets a bit more complicated to alter, but it can be done by resistor biasing the ADC pin to shift the voltage by the right amount.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
