NEXUS® NXEXP300 WATER LEVEL CONTROL

The Fireye NEXUS® NXEXP3000 is a microprocessor based, water level/draft control expansion module for use with the Fireye Nexus PPC6000 or integrated NX6100 series of parallel positioning controls.

Water Level/Draft Control Simplified

The latest addition to the NEXUS™
parallel positioning control family adds
dual functionality of Drum Level and
Draft Control to the already feature
packed 6000 series.

NXEXP300 Shown with Optional
NXDBWLC daughterboard Installed

Features & Benefits

• Boiler Water Level¹
One, two or three element boiler water
level control via 4-20mA inputs from
field devices. Feed pump VFD and pump
sequencing is also included.
• Sequence Draft Control²
Built in sequence draft control controls
the boiler outlet damper through prepurge,
light off and operation reducing standby
and operating losses.
• Total Dissolved Solid³
Industry standard TDS probe provides the
option to control surface blow down based
on TDS levels set by operators.
• Flexibility
Utilize proven Fireye CANbus servomotors
or industrial 4-20mA current or I/P feed
water valves.
• Wiring
International voltage setting and simple
four wire CANbus interconnections make
wiring a snap. Safety relay contacts can
be easily inserted into the existing control
wiring.
• Reliable Operation
Proven hardware with more than five years
of in field service has been reconfigured to
provide these additional features.
• Approvals
UL, FM, CE, SIL Level 2, SIL Level 3
pending review.
Overview
The NXEXP300 when combined with the Fireye PPC6000¹ or NX6100
parallel positioning system adds basic Water (Drum) Level Control, Sequence
Draft Control and Expanded Digital Inputs.
Basic water level control using a Fireye CANbus servomotor and suitable valve
can be controlled by one, two or three elements of the boiler system; drum
level, steam flow, feed water flow.
Sequence draft control is also standard with the NXEXP300. Utilizing a suitably
ranged differential pressure sensor and Fireye CANbus servomotor, controlling
the boiler outlet damper through pre-purge, light off and run couldn’t be
easier.
Also included are an additional seven low voltage and two line voltage safety
rated digital inputs. These inputs provide additional safety interlock annunciation
as well as position proving inputs for outlet dampers, combustion air makeup
dampers and/or user defined options.
The NSDBWLC optional daughterboard expands the basic water level control
to include measurement and control of boiler total dissolved solids (TDS) using
industry standard TDS probes³. The NXDBWLC has inputs for the TDS probe
as well as an RTD (PT100) type boiler temperature sensor. If no PT100 is available,
the NXDBWLC relies on the standard saturated steam table in it’s memory.
TDS’s are controlled by surface and or bottom blow down. A full range
options allows flexibility to meet most boiler requirements
Specifications and Performance
The Fireye NEXUS™ NXEXP300 is a microprocessor based, expansion module for use with the Fireye Nexus PPC6000¹ or integrated
NX6100 series of parallel positioning controls. The NXEXP300 expands the capability of the parallel positioning system by adding
valuable safety rated digital inputs, sequence draft control, boiler water level control and total dissolved solids (TDS) surface and
bottom blow down control. The small (5”L x 8.5”W x 3.75H) footprint, adjustable voltage (120/230, 50/60 hz.) and simplified wiring
provide easy retrofit to existing Fireye systems.
NXEXP300 Expansion Module
The NXEXP300 expands the capability of the NX6100/PPC6000¹ with seven low voltage,
safety rated, digital inputs along with two line voltage, safety rated digital inputs. When
configured via available option parameters, these inputs can be used to simply annunciate
conditions, or, shut the boiler down.
Sequence draft control is built into the NXEXP300 to control the boiler outlet damper. When
combined with an appropriate differential pressure sensor, Fireye servomotor or third party
actuator, the outlet damper will modulate and maintain the manufacturers’ outlet draft set point. The damper can be controlled with a
Fireye CANbus driven servo motor or, a third party actuator capable of accepting a 4-20mA signal. Analog control requires optional
NXDBWLC daughter board or optional NXDBVSD daughter board in main control. Maximum input impedance of actuators is 250
ohms. The boiler outlet damper is controlled during stand by, pre-purge, ignition and operation to provide a consistent outlet draft for
improved combustion performance and reduced stand by losses.
NXDBWLC Water Level Daughterboard
The option NXDBWLC expansion daughter board enhances the capability of the Nexus™
system by optimizing boiler water quality and level. The results are; higher quality steam and
reduced boiler water side scaling.
The NXDBWLC includes an input for the measurement of Total Dissolved Solids
(TDS) which in turn controls a surface, bottom or combination of, blow down valves.
A fully programmable operating scheme allows each site to be custom configured
based on water and operating conditions. Provisions are made for connecting a
PT100 RTD temperature sensor or the system can use a built in steam table for
estimating water temperature compensation. The NXDBWLC includes one analog
output for controlling either the boiler feed water valve or sequence draft damper.
The maximum input ompedance of the actuators must not exceed 250 ohms.
Other Enhancements:
• Oxygen Trim. 20+ Year Proven Oxygen Probe Technology
• VFD. Daughterboard for PPC6000/NX6100 Provides Two VFD
Channels Plus Modbus RTU

PPC 6000
Pub No.
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PPC-6001 PPC 6000 Series Fuel/Air ratio controller NXOG-6001 Operators Guide for PPC 6000 Series
NXPG-6001 Programming Guide for PPC 6000 Series MinOptP6000_6100 NEXUS NX6100/PPC6000 Minimum operation parameter setings setup

EXPANSION
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NXEXP-6001 NXEXP300 expansion unit for feed water and draft control for Fireye NX6100/PPC6000 NXESI-6101 External Servo Interface for NX6100 and PPC6000 Series


PPC4000/NXF4000
Click here to see the wiring video. /tr>
Pub No.
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PPC-PF PPC4000 Product Overview PPC4000-WD Wiring Diagram - PPC4000 with Burnerlogix or Flame Monitor
PPC-4001 PPC4000 Series Fuel Air Ratio Controller NXD-4101 NXD410 user interface used with PPC4000 fuel air ratio controller
NXCESO2-1001 NXCESO2 Oxygen Probe for use with PPC4000 Controller NXCESVFD-1001 NXCESVFD Plug-In Assembly for use with PPC-4000
MOD-4001 PPC4000 Modbus Communications NEX-3004 FX04 and FX04-1 Servo Motor Installation for PPC4000
NEX-3020 FX20 and FX20-1 Servo Motor Installation for PPC4000 NEX-3050 FX50 and FX50-1 Servo Motor Installation for PPC4000
NXTSD-4001 NXTSD4xx Touchscreen Installation Guide NXTSD-4002 NXTSD4xx Touchscreen Operators Guide
133-745 Installation sheet 133-745 59-562-2 cable for NXD410
user interface 133-747 129-192 For Use With FX04-1, FX20-1, FX50-1 SERVOS
133-748 59-565-X Cordset, 5 Conductors, Moulded Double End 133-750 35-381-2 O2 Probe Mounting flange for Use With NXCESO2 Oxygen Probe
133-751 Replacement cartridge for NXCESO2 Probe 133-755 129-194 SERVO CONNECTOR KIT for FX04, FX20, FX50
133-763 Installation replacement cooling fan for PPC4000 and NXCESO2 Probe SDReaderApp SD Card File Reader Application (zipped file)
133-765 Special instructions for using NXTSD407 & NXTSD413 displays NXF-4001 NXF4000 Series Fuel Air Ratio Controller with integrated flame safe guard.
NXCESAMP-1001                Plug-in amplifier for NXF4000 NXF4000-WD Wiring Diagram - NXF4000 Click here to see the wiring video.
NXF-PF NXF4000 Product Overview NXF-PPC4000-IN1 NXF4000 Vs PPC4000 comparison
NXF-PPC4000-IN4 NXF4000/PPC4000 Sensors NXF-PPC4000-IN2 NXF4000/PPC4000 displays
NXF-PPC4000-IN3 NXF4000/PPC4000 Servos/O2 Probe 
NXM2G
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NXM2G-1001 Intelligent boiler load control UL version NXM2G-1002 Intelligent boiler load control CE version




Accessories
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NEXBK-1000 Nexus Bracket and Coupling Accessories UC-4851 UC485 Optically isolated USB to RS422/RS485 converter
NEX-1502 ComFire 2 Combustion Analysis Tool 133-761 PXMS Pressure transmitter Installation Instructions
FXIATS-1 Ambient air temperature transmitter for use with the PPC4000 Series Fuel/Air Ratio Controller 




Danfoss VLT Drives
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176R0581 Danfoss HVAC Spec Sheet Setup Danfoss Drive Setup
176R0583 Danfoss HVAC Drive with EMB 
Nexus (3000/4000 Legacy)
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NEX-1001 Nexus Integrated Burner Control System, NX3100, NX4000, NX4100, NX5100, NX1466, NX1386, NX550, NX552, NX1021, NX1034, NX1030, NX1040, NX1044 NEX-1002 Nexus Expansion Interface and Expanded Burner Control System, NX280HW, NX280VSD, NX280ATI, NX280PK, NXA-CAB, NXA-PWS, NXA-PS500, NXA-PS1000
NEX-1502 ComFire 2 Combustion Analysis Tool NEX-2004 NEXUS NX04-1, -2 Servo Motor Installation, NX04-1, NX04-2
NEX-2020 NEXUS NX20-1, -2 Servo Motor Installation, NX20-1, NX20-2 NEX-2050 NEXUS NX50 -1, -2 Servo Motor Installation, NX50-1, NX50-2
NEX-3026 see obsolete NEX-2098 Nexus NX98 -1, -2 Servo Motor Installation, NX98-1
NEXBK-1000 Nexus Bracket and Coupling Accessories NEX-SO FIREYE ® Nexus and PPC5000 Boiler Sequencing
133-715 Instruction sheet for NX1021 / NX103x sensor NXQD-1000 Quick Disconnect Cordset & Receptacle, NXQD1FM, NXQD1M
NXMBIV2 Nexus Modbus Interface NXMBI-V2 


PPC 5000
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Product
PPC-5000 PPC 5000 Series Fuel/Air ratio controller, PXMS, PPC5000, AH21245, AH221244-002, AH221246-002, LA221419 NEX-SO FIREYE ® Nexus and PPC5000 Boiler Sequencing