GE Industrial Solutions Galaxy Pulsar Edge - Manual (Page 113)

Galaxy Pulsar Edge Power System Controller
Issue 3 October 2011
113
6 One-Wire Peripheral Devices
QS873A Voltage/Thermal Probes
The QS873A Voltage/Thermal Probes (VT-Probes) are used to measure battery temperatures for
slope thermal compensation, and to provide mid-string voltages to the ES771 for battery voltage
imbalance detection. Each of these weatherized assemblies monitor their respective contact
temperature and converts the measurements into serial data which is then read by the system
controller using Maxim’s industry standard 1-Wire® bus. Several QS873A probes can be
connected in a serial fashion since the data is received through digital means. The Pulsar Edge
system controller can handle up to 16 VT-probes. This allows multiple strings and or multiple
batteries within a string to be monitored for temperature. As mentioned, these probes are required
for the battery string voltage imbalance feature since they route the mid-string voltage to the
system controller via the ES771A remote mid-string voltage monitoring modules. All probes are
provided with a PTC device to protect against accidental short circuit during voltage
measurements.
Figure 6-1: QS873A Voltage/Thermal Probe (VT-Probe)
Following is a brief description of the interfaces on the QS873A VT-Probe depicted above.
J2
3-position connector connects the VT-Probe to the 1-Wire interface through cable 848719795. It
may also connect directly to the ES771A with (CC848791517, 2.5’) or (848719829, 10’) or other
VT-Probes in daisy chain fashion using either the (848719803, 5’) or the (848719811, 10’) cable.