OHAUS RI Series, Руководство по обслуживанию, Страница: 39 / 84

01/09/2006
Page - 39 -
10. Technical data Test points / Settings:
10.1
Electrical characteristics:
The scales can be powered from three different sources :
1- Mains (90 à 264 Volts AC / 47 à 440Hz).
A switching power supply unit converts the mains supply voltage to 18 Volts DC /3 A
which is used by the main board.
2-External battery of car (12 volts) or truck (24 volts).
3-Internal battery pack 13.2 Volts/3Ah.
When several supply are present at the same time the priority is the following:
1) External truck battery 24 Volts.
2) Mains.
3) External car battery 12 Volts.
4) Internal battery pack.
The internal battery pack is only used when there is no other supply source at the same
time.
When there is an other supply source this last one is detected by control signals: P_Sect
et P_Bat_Ext , The battery pack is insulated by an electronic switch in order to save its
energy.
Non interruptible power supply :
In case mains failure scales is automatically powered by the internal battery pack without
any interruption at the condition that both switches are "ON" at the same time .
Internal voltages :
A unique DC voltage between 11 et 30 Volts supplies the main board where internal
voltages are produced:
a) +3,3V (VCC to supply the µP and logical circuits and components).
b) +5V (motor interface, displays, thermal print head, serial port etc..)
c) +6,5V alimen3,3V, +5V, and + 5V dedicated to the load cell.
d) +24V / 5A by pulse for the printing.
RI Series and scales are fitted with two switches :
- Battery switch (at the top) allows to turn off external and internal battery pack .
- Mains switch (at the bottom) allows to turn off mains supply (diagram below)
NB: both switches can be activated at the same time .