Section 9 Other Accessories; Smart Management Module (Smm) - Generac Power Systems PWRcell Reference Manual

Other Accessories
Section 9

Smart Management Module (SMM)

Description
The Smart Power Management System is designed to
optimize the performance of a PWRcell Inverter system,
a standby generator, or both. The system can consist of
up to 8 individual Smart Management Modules (SMM).
Unlike other load management systems that depend on
another control device, the SMM modules are self-
monitoring and operate autonomously.
SMM modules monitor the frequency (Hz) of the power
being produced by a PWRcell Inverter system or standby
generator. If the frequency falls below a certain threshold,
the module will automatically
management algorithm to ensure that the inverter or
generator is not overloaded.
A PWRcell Inverter system identifies an overload
condition by monitoring current using the inverters CTs.
When current exceeds the inverters limit the inverter will
reduce it's frequency to below the trigger points of the
SMM.
Generator overload condition is determined by generator
frequency. Loads are shed when the frequency is <58 Hz
for 3.5 seconds or <50 Hz for 1 second. These same
frequency values apply to the inverter output.
The modules can be set to a load priority between 1 and 8
or be set in a lock out only mode for loads that do not need
to run during a power outage.
NOTE: PRIORITY MUST BE DIFFERENT for each
module in an installation. Priority sets the order in which
loads recover from a load shed event. Recovery time
from a load shed event is five minutes for Priority 1. Each
priority after Priority 1 waits an additional 15 seconds
after the initial recovery time. See
Table 1-1. Priority Settings
Priority
1
2 5 minutes 15 seconds
3 5 minutes 30 seconds
4 5 minutes 45 seconds
5
6 6 minutes 15 seconds
7 6 minutes 30 seconds
8 6 minutes 45 seconds
IMPORTANT NOTE: Early versions of the SMM use a
normally open (N.O.) contactor. Later versions use a
normally closed (N.C.) contactor with an added set of
mode selector jumper pins on the circuit board.
Diagnostic Repair Manual
follow a power
Table 1-1.
Recovery Time
5 minutes
6 minutes
Features and Controls
See Figure 9-1.
A
002518
F
Figure 9-1. SMM Features and Controls
Priority Dial (A) – Sets module priority.
Lockout Switch (B) – Initial switch to generator power
will allow load to operate until an overload condition
occurs. If overload happens the load will be locked out
until utility returns. See
NOTE: Early Version: When lockout switch is engaged
and running on generator, module will start in load shed
mode. After approximately 1 minute of run time the
module will enter lockout mode. When utility returns while
in lockout mode, the module will delay for 2 minutes
before returning to load shed mode. After a 4 minute
timer expires the load will be activated.
Test Button (C) – Disables contactor output for a
specified time.
LED (D) – Provides module status. See
Contactor (E) – Controlled by a smart controller in
module. Contactor remains CLOSED until generator
power is required. Upon generator/inverter activation,
controller moves to OPEN to handle overload conditions.
NOTE: When the system is on generator or inverter
power, the contactor is also opened during lockout switch
ACTIVE state.
Mounting Holes (F) – Internal enclosure mounting holes
provide clean and sturdy mounting.
Recovery time is based on priority dial settings. See
Table 1-1.

Section 9 Other Accessories

B C
D
E
Setting Lockout.
Table 1-5.
F
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