Setting Up (Pm-Pc); Exercise; Serial Communications; Genlink - Generac Power Systems PowerManager PM-PC Manual

PowerManager™ provides a load shed signal feature. If one of the
generators fails to start, PowerManager™ sends this signal to initi-
ate load shedding, if installed. If any power module has a control
unit or contactor problem and cannot close onto the generator bus
at startup or during operation, PowerManager™ will also send the
load shed signal.
Load Shedding is able to be programmed based on power needs
and generator rated power available. Therefore, some systems
may be able to lose 1 or more generators, but still not shed any
load.

SETTING UP (PM-PC)

After the unit has been installed along with the PowerManager™
transfer switch (see PowerManager™ manual), set the keyswitch-
es to automatic mode. The PowerManager™ will start the genera-
tors as necessary.

EXERCISE

The Generators should be programmed to exercise via GenLink™.
For PM-PC, this is done by giving commands to the PowerManager™
through GenLink™ (see the PowerManager™ manual). For PM-GC,
this is done via the Exercise Configuration settings in the PM-GC.

SERIAL COMMUNICATIONS

The control panel has two RS-232 and two RS-485 communica-
tion ports. In the MPS system, one RS-485 port is used to com-
municate to the PowerManager™, and one to the touchscreen.
One RS-232 port is configured to talk to GenLink™ on a PC and
the other is used for deep diagnostics. This port can be reconfig-
ured to be a Modbus slave and can be used to communicate with
other systems such as building management. A remote annuncia-
tor can be connected either to this spare port (for individual annun-
ciation - a RS-232/485 converter is needed) or a communal
annunciator can be connected to the PowerManager™ port. In this
case, the PowerManager™ does an "OR" function of each genera-
tor's alarms, and then sends the result to the communal annuncia-
tor. Multiple annunciators can be connected to the same port, but
they will all annunciate the same thing - either communal results
or individual results.
Communications are done via Modbus RTU protocol.

GENLINK™

The control panel can communicate with GenLink™ which is a PC
based program allowing both the interrogation of the generator and
remote programming of its parameters. The user will be able to
start and stop the generator if it is in AUTO mode. GenLink™ com-
munications will normally be via the GenLink™ connection port
situated on the relay box for a PM-GC or via the PowerManager™
for a PM-PC. The version of GenLink™ that works with the PM-GC
and the PM-PC systems is not the same as older versions of
GenLink™, It is called "GENLINK-DCP".

METHOD OF CONNECTION

The MPS PM-PC is used in conjunction with Generac's
PowerManager™ product. Each PM-PC will communicate with the
PowerManager™ via the RS-485 port. GenLink™ will communi-
cate with the PM-PC via the PowerManager™. Multiple generator
sets can be linked to the PowerManager™ via this port, and
GenLink™ can interrogate each one individually. GenLink™ can
also communicate locally (individually) via a laptop to the RS-232
port (if no other devices are connected). A building management
system can connect to the PowerManager™ module via the spare
RS-232 port (deep diagnostic - a RS-232/485 converter may be
needed) on the PowerManager™ module.

ADDITIONAL PANEL COMPONENTS

In addition to the control module, the PM-PC/GC contains the fol-
lowing components (see Figure 9):

ALARM HORN

This horn sounds an audible warning when an alarm condition
exists. See the "Alarms" section for further information.

EMERGENCY STOP SWITCH

When pressed, this switch will automatically shut down the entire
generator set. The operator must pop the switch out to its original
position, and clear the E-stop Alarm to reset it and allow for gen-
erator operation.

RELAY/FUSE BOX

The relay box houses all slave relays for engine components (for
example, starter relay, run relay, pre-heat relay, etc.). The DC panel
fuses are also mounted inside this box.

VOLTAGE SENSING MODULE

This circuit monitors the three-phase alternator output and bus
voltages. These high voltages (480, 208 etc.) at the input to the
circuits, are electronically conditioned to produce low voltage out-
puts (typically 5v rms) which are proportional to the alternator and
bus voltages. The outputs are used by the PM-GC or PM-PC con-
trol modules to determine the phase and amplitude of the sources.
Operation
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