GE Industrial Solutions Galaxy Pulsar Edge - Manual (Page 116)

Galaxy Pulsar Edge Power System Controller
Issue 3 October 2011
116
ES771A Remote Mid-String Voltage Monitor
Module
The ES771A remote mid-string voltage monitoring module is used to measure the mid-string
voltages of up to three strings of batteries. This unit utilizes an appropriate QS873A VT-Probe
connection to obtain the voltage for measurement. It then serially transmits the appropriate
information to the system controller which performs the voltage imbalance detection feature. It
also serves as interface that transmits the thermal data from the VT-Probes for slope-thermal
compensation and other battery management features. As with the QS873A VT probes, ES771A
units also utilize Maxim’s industry standard 1-Wire® bus. Thus, multiple ES771A devices can be
used and placed in a daisy chain fashion along with the QS873A VT probes. The number of Mid-
string voltage modules actively hooked to batteries and being monitored by the system controller
to batteries is displayed under Batteries in the Status menu. Note: VT-Probes must be connected
to the batteries in order for the ES771 to be recognized.
The Pulsar Edge can monitor up to six ES771A modules. Each ES771A module is individually
addressed so that specific mid-string voltages can be displayed and identified. A seven-position
rotary ID switch located on the unit must be set to a unique address number otherwise an ID
conflict alarm will be generated. Units are shipped out of the factory with a default ID setting of
“one”. If additional units are to be in the system the ID must be reconfigured. Note: there are
systems that are shipped with ES771A units installed and with proper configuration.
Figure 6-3: ES771A Remote Voltage Monitor Module
Following is a brief description of the interfaces on the QS873A VT-Probe depicted above.
J10, J20
RJ-45 receptacles that connect the ES771A to other ES771As or the 1-Wire interface port of the
controller or system provided 1-wire interface. Typical cables utilized are the (CC848791500, 4”)
or (848652947, 10’) cable.
J30
Connects the ES771A to the first QS873A VT-Probes using either the (CC848791517, 2.5’), the
(CC848797290, 6’) or the (848719829’, 10’) cables.
J1, J2, J3
Snap-fit connectors for the mid-string voltage signal wire (Brown) from the VT-Probes.