P-K SOLIS™
Gas Fired Boiler
Technical Service 1.877.728.5351
Revised: March 15, 2021
Released: March 15, 2021
Patterson-Kelley 2021
All Rights Reserved.
2701000090 P-K SOLIS NURO Installation and
Owners Manual (Rev A).docx
Page 15
Power Requirements (SL-2500 & SL-3000)
The SL-2500 and SL-3000 boilers can be manufactured for 208-240 VAC,
three phase
, 60 hertz
electrical service
OR
440-480VAC, three
phase, 60 hertz electrical service. The total operating
amperage is indicated on the rating nameplate and the SL-2500 & SL-3000 boiler models require less
than 20 Amps at full load. Before starting the boiler, check to ensure that the proper electrical service is
connected to the boiler.
An external electrical disconnect and overload protection (not supplied with the boiler)
are required
.
Refer to Section
7.2
, for proper wiring and configuration of the electrical connections. The electrical
service to the boiler must be installed and grounded in accordance with local codes or in the absence of
such requirements, in the U.S. with National Electrical Codes, ANSI/NFPA No. 70 latest edition or, in
Canada, to the current Canadian Electrical Code, Part I, CSA C22.1 latest edition. Installed conduit
must not block any of the boiler’s openings and must allow the front door to be opened.
Three Phase Power Supply Connection (SL-2500 & SL-3000)
Main Power Connection Box
Always check the rating nameplate of the SL-2500 & SL-3000 boiler to determine the required electrical
service:
•
208-240VAC, three phase, 60 hertz
•
440-480VAC, three phase, 60 hertz
The incoming three phase power for the SL-2500 & SL-3000 boilers is connected to the terminal strips
on the rear of boiler and the Ground terminal located in the main power connection box. The images
on the next page show the Low Voltage (TB1) and High Voltage (TB2) terminal blocks (back panel
hidden for clarity) plus the
Main Power Connection Box
on the SL-2500 & SL-3000 with the front door
hidden for clarity:
•
Terminal 1 = HOT L1
•
Terminal 3 = HOT L2
•
Terminal 5 = HOT L3
•
Terminal G = GROUND
Control Transformer
The
Main Power Connection Box
features a
Control Transformer
which steps down two hot leads
from the incoming three-phase power in order to supply 110-120VAC single phase power to the
NURO
®
control system. Be aware that SL-2500 & SL-3000 boilers ordered in the 240V configuration,
are pre-wired from the factory for operation with 240 VAC three phase incoming power.
NOTE:
The SL-2500 & SL-3000 boiler models
MUST
be ordered to the correct voltage!
IT IS NOT
POSSIBLE
to convert an SL-2500 & SL-3000 between the 240V and 480V configurations in the
field!
NOTICE:
If 208 VAC three phase power is supplied to the boiler, the internal control transformer
must be re-wired
for operation at this lower voltage. The wire
in terminal X3 on the load side of the
internal control transformer must be moved to terminal X4. This supplies 110 VAC power to the
NURO
®
control from the 208 VAC main voltage.
Refer to Section
7.2.4
for proper wiring and
configuration of
the internal control transformer.
