Hi everyone, help me to switch NTS 450 intverter to use with li-ion cells, from box it has 10.5V low level switch off, and in manual written that inverter is suits to li - ion, i need to set low level of input voltage to 9 volts, how can i do this?
I connect invertor to UART, but it responds only for commads “Q” and “I” and thats all
Tnx for help
Hello,
Are you looking at the NTS-450-112US or NTS-450-224EU?
Greetings,
The product installation manual found here may be useful, particularly the section regarding the serial interface. An improperly formatted message or checksum will prevent the device from responding as desired when trying to change settings.
The operating limits of the device are given in the specifications table: the permitted input range for a nominal 12v input device is 10 to 16.5V, with output de-rating below 10.5V input.
How “suitable” that is for use with a 3-cell lithium ion source is debatable. A 4-cell LiFe3PO4 source would seem like a better match.
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NTS-450-224EU
Hi there,
Manufacturer declare that is suitble for li-ion, with 3 cells low level must be 9 v, and with 4 cells high level must be 16.8 volts, i think there must be some programmable adjustment of low and high level of input voltage.
I might be wrong, but I’m getting the impression the lowest you can get that shutdown voltage per the manual is 10V plus or minus 0.3V
Page 25 of the manual linked appears to show the format of the data packet one would send to adjust the soft settings. The lowest valid value for undervoltage shutdown would appear to be 9.7v. The datasheet figure Kristof references would seem likely to refer to a factory default setting.
Unfortunately, marketing departments often write the first page of a datasheet. What’s found there may or may not have real meaning, and as a general rule it is not considered part of a device specification.
Interesting… I would not have thought to look for such a thing.
It seems likely that this is an adjustment for calibrating the device’s measurement of input voltage.
Please keep in mind that as input voltage drops, the amount of current required to supply a given output load increases proportionally, and that losses due to resistance in the device increase as current2. Having reverse-engineered a few devices from this manufacturer after failure, I would say that they seem to be designed with very little room for operation outside of the stated specifications.
Please take care to limit the load placed on the device when the supply voltage is low.