Black Box GEH-6510 - Manual (Page 13)

DDE Server User’s Guide Chapter Two - Overview •••• 9
Devices
Power-management devices are primarily measurement devices – they measure a
wide variety of power-related data or control data describing what is happening at a
device. This data can be read remotely (over a network) by power-management
software, such as the PMCS DDE Server.
The data read by these devices is stored in registers, which are special, defined spots
in the device’s memory. A list of these registers and their contents is called a register
map. Figure 3 is an illustration of a register map. A client sends a request to the
Server for data from a particular device. The Server knows the register map of the
device and requests the register block containing the requested data.
PMCS
DDE Server
POWER LEADER EPM
Register Map
1010
1076
.
.
.
.
.
.
.
.
DDE client application
Current Phase A: ___
Voltage Phase A: ___
DDE client application
Ground Fault Trips Count: ___
Number of Operations: ___
1056
1061
Enhanced MicroVersaTrip
Register Map
.
.
.
.
.
.
.
.
Figure 3. Sample register map.
The register maps for each device are programmed into the PMCS DDE Server. The
Server is then able to transform a client application’s request for “kilowatt hours at
North_Meter” into a request sent to that specific device for the contents of a specific
register; the client doesn’t need to know which register contains what information,
merely what information is needed from which device. The PMCS DDE Server takes
care of the details, and after a request for data has been placed, the Server continues
to monitor that data from the particular device, updating the client application with
any changes to the data.
The register maps of the POWER LEADER TM family of devices and a variety of
other devices are pre-configured in the Server. If you wish to use a device whose
register map is not pre-configured, you need to supply the appropriate register
information to the Server so it will know where in the device’s memory to get the
information you are requesting. We’ll refer to these as generic devices since we don’t
know what they might be. Defining new device types is detailed in Chapter 6,
Advanced Options.