upsc: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/upsc - from package: nut-client

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/bin/upsc - from package: nut-client

You may install the required package with command apt-get install {package}

Error in other languages:
upsc: bevel nie gevind nie
upsc: comandă negăsită
upsc: comando não encontrado
upsc: commande introuvable
upsc: command not found
upsc: käsku ei ole
upsc: không tìm thấy lệnh
upsc: komanda nerasta
upsc: Kommando nicht gefunden.
upsc: kommandot finns inte
upsc: komut yok
upsc: nie znaleziono polecenia
upsc: níor aimsíodh an t-ordú
upsc: no se encontró la orden
upsc: no s'ha trobat l'ordre
upsc: opdracht niet gevonden
upsc: parancs nem található
upsc: perintah tidak ditemukan
upsc: príkaz nenájdený
upsc: příkaz nenalezen
upsc: команда не найдена
upsc: командата не е открита
upsc: 命令找不到
upsc: コマンドが見つかりません