Section 8: Rechargeable battery measurements
Model 2450 Interactive SourceMeter® Instrument User's Manual
8-4
2450-900-01 Rev. C / December 2013
Figure 36: Schematic for the battery charge and discharge cycle test
Hazardous voltages may be present on all output and guard terminals. To prevent electrical
shock that could cause injury or death, never make or break connections to the Model 2450
while output is on.
To prevent electric shock, test connections must be configured such that the user cannot
come in contact with conductors or any device under test (DUT) that is in contact with the
conductors. It is good practice to disconnect DUTs from the instrument before powering the
instrument. Safe installation requires proper shields, barriers, and grounding to prevent
contact with conductors.
There is no internal connection between protective earth (safety ground) and the LO
terminals of the Model 2450. Therefore, hazardous voltages (more than 30 V
rms
) can appear
on LO terminals. This can occur when the instrument is operating in any mode. To prevent
hazardous voltage from appearing on the LO terminals, connect the LO terminal to
protective earth if your application allows it. You can connect the LO terminal to the chassis
ground terminal on the front panel or the chassis ground screw terminal on the rear panel.
Note that the front-panel terminals are isolated from the rear-panel terminals. Therefore, if
you are using the front-panel terminals, ground to the front-panel LO terminal. If using the
rear-panel terminals, ground to the rear panel LO terminal.
You can make test connections to the Model 2450 from the rear or front panel of the instrument.
The basic connection configurations for the Model 2450 include:
•
Two-wire sensing
•
Four-wire remote sensing
•
Guard
Connect the Force HI and Sense HI output terminals of the Model 2450 to the positive (+) terminal of
the battery. Connect the Sense LO and Force LO outputs to the negative (
−
) terminal of the battery.
Make sure that when the output of the Model 2450 is turned off, it is set to the high-impedance
(High-Z) output-off state. When the high-impedance output-off state is selected, the output relay
opens when the output is turned off. This prevents the battery from draining when the output is off.
