Johnson Controls F4-SNC User manual

F4-SNC Installation Guide
Application
The Facility Explorer SNC Series (F4-SNC) are Ethernet-
based, supervisory controllers that connect Building
Automation System (BAS) networks to IP networks.
The SNC features onboard inputs and outputs for
direct control of equipment. This device monitors and
controls networks of field-level building automation
devices, including HVAC equipment, lighting, security,
and fire safety equipment. The SNC has FIPS 140-2 Level
1 Compliance, which is a United States government
cybersecurity standard that approves cyroptographic
modules/algorithms used for encryption.
The F4-SNC25151-0H and F4-SNC25151-04H models have a
display where you can view Alarms, Overrides, Equipment
Data, and Trends. You can command Equipment Data
points. Display settings can be viewed and edited but
Controller settings can only be viewed. You can navigate
the display using the direction arrows, back, OK, and menu
buttons.
The F4-SNC25151-0x/x models have a total of 40 I/O points
- with 25 inputs and 15 outputs. The F4-SNC16121-0x
models have a total of 28 I/O points - with 16 inputs and
12 outputs. The first two numbers of the product code
number represent the number of inputs (SNC25151-0x/
x) and the next two numbers represent the number
of outputs (SNC25151-0x/x). The SNC offers various
integration options.
Field Bus integrations supported
• BACnet MS/TP
Ethernet integrations supported
• BACnet/IP
Physical features
The following figures display the physical features of the
SNC25151-0x/x and SNC16121-0x with display models. The
accompanying table provides a description of the physical
features and a reference to further information where
relevant.
Note: The physical features labelled with callouts
9-16 are only available on SNC models with the
display.
Figure 1: F4-SNC25151-0x/x
*241014302031A*
Part No. 24-10143-02031 Rev. A
2020-11-11
(barcode for factory use only)
F4-SNC25151-0xx, F4-SNC16121-0x

Figure 2: F4-SNC16121-0x
Table 1: Physical features of the SNC25151-0x and
SNC16121-0x
Callout Physical features
1
Binary Outputs (BO) removable terminal
blocks. See Connecting input and output
terminals for more information.
2
Configurable Outputs (CO) removable
terminal blocks. See Connecting input and
output terminals for more information.
3
Analog Output (AO) removable terminal
blocks. See Connecting input and output
terminals for more information.
4
Rotary switch dials: controller number. Ships
from the factory at setting 000. See Rotary
switch dials for more information.
5Supply power removable terminal block:
gray terminals; 24 VAC, Class 2.
6
Two Universal Serial Bus (USB) 2.0 host type
A ports.
USB-1 (top port): Any Johnson Controls
approved USB device can be connected to
the top port.
USB-2 (bottom port): Any non-wireless,
Johnson Controls approved USB device can
be connected to the bottom port.
Note: There is one micro-USB port that
is reserved for future use.
7Sensor/Actuator (SA) Bus port: RJ12 6-Pin
Modular Jack.
Table 1: Physical features of the SNC25151-0x and
SNC16121-0x
Callout Physical features
8Field Controller (FC) Bus port: RJ12 6-pin
Modular Jack.
9
Field Controller (FC) Bus removable terminal
block: blue terminal. See FC Bus terminal
block for more information.
10 End-of-Line (EOL) switch.
11
Sensor Actuator (SA) Bus removable
terminal block: brown terminal. See SA Bus
terminal block for more information.
12
Binary Input (BI) removable terminal blocks.
See Connecting input and output terminals
for more information.
13 SNC input terminal blocks cover
14
Universal Inputs (UI) removable terminal
blocks. See Connecting input and output
terminals for more information.
15
Two active Ethernet ports, 1000/100/10
Mbps; 8-pin RJ45 connector, labeled ETH-1
(top) and ETH-2 (bottom).
16 Multi-color LED status indicators. See LED
status indicators for more information.
17 Reset button. See Reset button for more
information
18 Recovery button. See Recovery button for
more information.
F4-SNC Installation Guide2

Installation
Follow these guidelines when you transport and use the
SNC:
• Transport the SNC in the original container to minimize
vibration and shock damage to the SNC.
• Verify that all the parts shipped with the SNC are
present.
• Do not drop the SNC or subject it to physical shock.
• Do not use non-qualified USB adapters in the two
USB ports. The USB ports only function with the USB
adapters that are tested and qualified for use on the
SNC. Non-qualified adapters do not function in the USB
ports of the SNC. See Accessories ordering information
for the list of qualified and supported USB adapters.
Important: Do not open the housing for any reason.
The supervisory controller has no user-serviceable
parts inside. Tamper-evident labels on the device
caution installers, service technicians, building
owners, and our RMA inspectors from unauthorized
opening or tampering of the device.
Parts included
• One SNC
• One installation sheet
Materials and special tools needed
You can mount the SNC by using the fasteners option or
the DIN rail option.
• Fasteners option - Three fasteners appropriate for the
mounting surface:
- #8 screws - North America
- M4 screws - Europe
• DIN rail option - 20.3 cm (8 in.) DIN rail for DIN rail
mount applications only.
Mounting
Location considerations
Follow these guidelines when you mount an SNC:
• Ensure that the mounting surface can support the SNC
and any user-supplied enclosure.
• Mount the SNC in the proper orientation (horizontal
preferred, vertical acceptable).
• Mount the SNC on an even surface in wall mount
applications whenever possible.
• Mount the SNC in areas free of corrosive vapors and
observe the environmental limitations listed in the SNC
technical specifications section.
• Do not mount the SNC on surfaces that are prone
to vibration, such as duct work, or in areas where
electromagnetic emissions from other devices or wiring
can interfere with SNC communication.
• Allow sufficient space for cable and wire runs and
terminal connections.
• Mount the power supply above the SNC to ensure
adequate heat dissipation and to position close to the
power wiring conduit.
• Do not install the SNC in an airtight enclosure. Make
sure the enclosure offers sufficient ventilation to
ensure the temperature in the enclosure does not
exceed 50°C (122°F).
• Mount the SNC so that the enclosure wall or the
transformer does not obstruct ventilation of the SNC
housing.
Dimensions
Figure 3: SNC mounting dimensions, in. (mm)
F4-SNC Installation Guide 3

Mounting the SNC for wall mount
applications
Use the holes in the three mounting clips for wall mount
applications. To mount the SNC on a vertical surface,
complete the following steps:
1. Pull the top mounting clip upwards to the extended
position.
2. Mark mounting hole locations on the wall using the
dimensions shown in Figure 3, or hold the bracket
against the wall and mark the hole locations through
the mounting clips. The screw holes on the SNC
accommodates M4 and #8 screws.
3. Drill holes in the wall based on the locations marked
in Step 2. Insert wall anchors for each hole if
necessary.
4. Hold the device in place, insert the screws through
the mounting clips and into the screw holes, and
then carefully tighten all screws.
Important: Do not overtighten the mounting
screws. If you overtighten the screws, you can
crack the mounting clips.
Mounting the SNC for DIN rail mount
applications
About this task:
To mount the DIN rail and the SNC, complete the
following steps:
1. Securely mount a 20.3 cm (8 in.) DIN rail in the
required space.
2. On the SNC, extend the two bottom mounting clips.
3. Hang the SNC on the DIN rail hooks on the back of
the SNC.
4. Press the DIN clips back into position to secure the
unit on the DIN rail.
Mounting the SNC in a panel
To mount the SNC in a panel, follow these requirements:
• Mount the panel in accordance with the manufacturer’s
instructions.
• Mount the SNC in the panel following the guidelines in
Location considerations.
Wiring overview
Power supply, network, and
communication connections
See for the location of the power supply terminal, FC Bus
and SA Bus terminals, Ethernet ports, and USB ports. All
terminal blocks are removable terminal blocks.
Power supply
Power the SNC with a 24 VAC power transformer. In North
America, use a Class 2, 24 VAC power supply with a 50
VA minimum output. Outside North America, use a 24
VAC SELV (safety extra-low voltage) transformer at the
appropriate rating. The minimum input voltage for the
SNC to operate properly is 20 VAC.
Use a dedicated power supply to the SNC only. Do not
connect any other loads to the power supply. Additional
loads may cause noise interference. Outputs should be
powered from a separate source when not using internal
power.
Ethernet port
The Ethernet port is an 8-pin RJ45 network port used to
connect the SNC to Ethernet IP networks. You can connect
the SNC to Ethernet networks at 1000, 100, or 10 Mbps.
The maximum allowable cable length is 100 m (328 ft).
There are two active Ethernet ports on the SNC25151-0x/x
and SNC16121-0x models that you can use to daisy-chain
BACnet/IP devices.
FC Bus terminal block
The SNC has one Field Controller (FC) Bus terminal
connection. The connection uses the blue 4-pin
removable, terminal block that is labeled FC BUS.
The FC Bus connection is an isolated RS-485 port with
4-pin terminal blocks that can communicate at 76,800,
38,400, 19,200, 9600, or 1200 baud. Use the FC Bus port
to integrate BACnet MS/TP controller networks into the
Facility Explorer system.
Note: The FC Bus is not enabled by default when
shipped from the factory.
The SHD (shield) connection on the FC terminal block is
not connected to any earth ground connection.
SA Bus terminal block
The SNC has one SA Bus terminal block connection. The
connection uses the orange 4-pin SA Bus removable,
terminal block that is labeled SA BUS. Connect the 4-wire
SA Bus cable to the SA BUS terminal block.
USB ports
The SNC features two USB 2.0 host (type A) ports that are
disabled by default. You must activate the USB ports in
the Site Management Portal (SMP). The two USB ports
labeled USB-1 and USB-2 are both configured as hosts
and are independent of each other. Use the USB ports to
connect an integration adapter.
Important: Do not connect any other loads to the
USB ports. For example, do not power cell phones
from the USB ports.
See Accessories ordering information for more
information on the adapters.
Wiring the SNC
Mount the SNC securely before you wire it. For details, see
Location considerations.
F4-SNC Installation Guide4

CAUTION
Risk of Property Damage.
Do not apply power to the system before checking
all wiring connections. Short circuited or improperly
connected wires may result in permanent damage to
the equipment.
Attention
Risque de dégâts matériels.
Ne pas mettre le système sous tension avant
d'avoir vérifié tous les raccords de câblage. Des
fils formant un court-circuit ou connectés de façon
incorrecte risquent d'endommager irrémédiablement
l'équipement.
WARNING
Risk of Electric Shock.
Disconnect or isolate all power supplies before
making electrical connections. More than one
disconnection or isolation may be required to
completely de-energize equipment. Contact with
components carrying hazardous voltage can cause
electric shock and may result in severe personal injury
or death.
WARNING
Risque de décharge électrique.
Débrancher ou isoler toute alimentation avant
de réaliser un branchement électrique. Plusieurs
isolations et débranchements sont peut-être
nécessaires pour -couper entièrement l'alimentation
de l'équipement. Tout contact avec des composants
conducteurs de tensions dangereuses risque
d'entraîner une décharge électrique et de provoquer
des blessures graves, voire mortelles.
Important: Use this SNC only as an operating
control. Where failure or malfunction of the SNC
could lead to personal injury or property damage
to the controlled equipment or other property,
additional precautions must be designed into the
control system. Incorporate and maintain other
devices, such as supervisory or alarm systems or
safety or limit controls, intended to warn of or
protect against failure or malfunction of the SNC.
Important: Utiliser ce SNC uniquement en tant
que dispositif de contrôle de fonctionnement.
Lorsqu'une défaillance ou un dysfonctionnement
du SNC risque de provoquer des blessures ou
d'endommager l'équipement contrôlé ou un
autre équipement, la conception du système de
contrôle doit intégrer des dispositifs de protection
supplémentaires. Veiller dans ce cas à intégrer de
façon permanente d'autres dispositifs, tels que
des systèmes de supervision ou d'alarme, ou des
dispositifs de sécurité ou de limitation, ayant une
fonction d'avertissement ou de protection en cas de
défaillance ou de dysfonctionnement du SNC.
Important:
• Do not apply power to the SNC before you
complete and check connections. Short circuits
or improperly connected wires may result in
permanent damage to the equipment.
• Use copper conductors only. Make all wiring in
accordance with local, national, and regional
regulations.
• The SNC is a low-voltage device. Do not exceed
the SNC electrical ratings. Applying high voltage
to the SNC will void any warranties and may result
in permanent damage.
• Prevent any electrostatic discharge (ESD) to the
SNC. Static electric discharge can damage the SNC
and void any warranties.
Follow these guidelines when you wire the SNC:
• Route the supply power wires and communication
cables at least 50 mm (2 in.) away from the vent slots in
the sides of the SNC housing.
• Provide slack in the wires and cables. Keep cables
routed neatly around the SNC to promote good
ventilation, LED visibility, and ease of service.
• Ensure that the building automation network wiring
meets the specifications, rules, and guidelines in Wiring
considerations and guidelines.
• Follow the transformer manufacturer’s instructions
and the project installation drawings. Power supply
wire colors may be different on transformers not
manufactured by Johnson Controls.
• Verify that transformer phasing is uniform across the
devices. Power network devices with uniform 24 VAC
supply power phasing to reduce noise, interference,
and ground loop problems.
• Do not connect the SNC to an earth ground connection.
Connecting to the FC Bus port
The FC Bus port is an RJ12, 6-position modular jack that
provides a connection for the Mobile Access Portal (MAP).
The FC Bus port is connected internally to the FC Bus
F4-SNC Installation Guide 5

terminal block and so they share only one communication
protocol. See Communications Bus and supply terminal
blocks, functions, ratings, requirements, and cables for
more information. The FC Bus port pin assignment is
shown in Figure 4 and Table 2.
Figure 4: Pin number assignments for FC Bus port or
SA Bus port
Table 2: Pin number assignments for FC Bus port or SA
Bus port (RJ12 modular jack)
Callout Signal
1 FC Bus or SA Bus (+)
2 FC Bus or SA Bus (-)
3 Bus and Power Common
4 Power (15 VDC)
5 Bus and Power Common
6 Power (15 VDC)
Connecting to the FC Bus terminal
About this task: To connect devices to the FC Bus,
complete the following steps:
1. Connect the 3-wire bus cable to the removable blue
4-pin terminal block labeled FC BUS as shown in
Figure 5.
Figure 5: FC Bus terminal block and wiring connections
2. Set the FC EOL switch to the proper position. See
the note in Setting the EOL switch.
3. Go to Connecting the power source.
Connecting to the SA Bus port
The SA Bus port is an RJ12, 6-position modular jack that
provides a connection for the MAP, or other SA Bus
devices with RJ12 plugs.
The Sensor port is connected internally to the SA Bus
terminal block. See Communications Bus and supply
terminal blocks, functions, ratings, requirements,
and cables for more information. The SA Bus port pin
assignment is shown in Figure 4 and Table 2.
Connecting to the SA Bus terminal
1. Connect the 4-wire bus cable to the removable
orange 4-pin terminal block Sensor/Actuator (SA)
Bus, labeled SA BUS.
Note: Only connect terminal devices to either
the SA Bus port or to the SA Bus 4-pin terminal
block, not both.
Figure 6: SA Bus terminal block wiring
2. Go to Connecting the power source.
Connecting the power source
1. Connect power to the SNC using a 24 VAC power
transformer, connect the 24 VAC supply power
wires from the transformer to the gray 2-pin
terminal block labeled 24 V~ on the SNC (Figure 7
and Table 3 ). The connections are HOT and COM
(common).
Note: Power supply wire colors may be
different on transformers not manufactured
by Johnson Controls. Follow the transformer
manufacturer’s instructions and the project
installation drawings.
F4-SNC Installation Guide6

Figure 7: Supply power wiring (24 VAC transformer) Table 3: Power source connection detail
Callout Description
1 Brown wire (COM)
2 Orange wire (24 VAC)
3Wires from Johnson Controls 24 VAC, Class Power
Transformer
Connecting input and output terminals
The SNC25151-0x/x supports up to 40 hard-wired onboard I/O points, 25 inputs and 15 outputs.. The SNC1612x supports
up to 28 hard-wired onboard I/O points, 16 inputs and 12 outputs.
Table 4: Onboard I/O points
SNC Total I/O Universal
Inputs (UI)
Binary Inputs
(BI)
Configurable
Outputs (CO)
Analog
Outputs
(AO)
Binary
Outputs (BO)
SNC25151-0x/x 40 14 11 4 4 7
SNC16121-0x 28 10 6 4 4 4
Note: The SNC has two sets of 24+ and common
terminal block connections amongst the output
pins (Label numbers 19, 20 and 25, 26). The 24 V
connection (Label numbers 20 and 26) is the same as
the 24V~ HOT connection (Label number 02) and the
COM connections (Label numbers 19 and 25) are the
same as the 24VAC~ COM connection (Label number
01). These extra power connections can be used to
jumper power for switched high (externally sourced)
or switched low (externally sourced) Triac loads.
Table 5: Input and output terminals
Type of Point Options
Universal Inputs
• Voltage Analog inputs (0-10 VDC)
• Current Analog inputs (4-20 mA)
• Resistive Analog inputs (0-2k Ohm)
- RTD: 1k Nickel, 1k Platinum, or A99B SI
- NTC: 10k Type L or 2.225k Type 2
• Dry contact Binary inputs
Binary Inputs • Dry contact maintained
• Pulse counter mode (100 Hz)
Configurable
Outputs
• Voltage Analog outputs (0-10 VDC)
• Binary Outputs (24 VAC Rated Triac)
Analog Outputs • Voltage Analog outputs (0-10 VDC)
• Current Analog outputs (4-20 mA)
Binary Outputs 24 VAC Rated Triac
Terminal functions, ratings, requirements, and wiring guidelines
F4-SNC Installation Guide 7

Input and output wiring guidelines
The following table provides information and guidelines
about the functions, ratings, and requirements for
the SNC input and output terminals and references to
guidelines for determining proper wire sizes and cable
lengths.
In addition to the wiring guidelines in the following table,
observe these guidelines when wiring inputs and outputs:
• Run all low-voltage wiring and cables separate from
high-voltage wiring.
• Ensure all input and output cables, regardless of wire
size or number of wires, consist of stranded, insulated,
and twisted copper wires.
• Shielded cable is recommended but not required for
input or output cables.
• Shielded cable is recommended for input and output
cables that are exposed to high electromagnetic or
radio frequency noise.
• Inputs/outputs with cables less than 30 m (100 ft)
typically do not require an offset in the software setup.
Cable runs over 30 m (100 ft) may require an offset in
the input/output software setup.
Terminal wiring and cable length guidelines
Table 6: Terminal wiring
Terminal block label Terminal labels Function, ratings, and
requirements
Determine wire size and
maximum cable length
+15 V
15 VDC Power Source for active
(3-wire) input devices connected
to the Universal UI-# terminals.
Provides 100 mA total current.
Same as Universal inputs UI-#
Note: Use a 3-wire cable
for devices that source
power from the +15 V
terminal.
Analog Input - Voltage Mode
(0–10 VDC)
10 VDC maximum input voltage
Internal 110k Ohms Pulldown.
See Guideline A in Table 7.
Analog Input - Current Mode
(4–20 mA)
Internal 100 Ohms load
impedance.
See Guideline B in Table 7.
Analog Input - Resistive Mode
Internal 12 V, 15k Ohms pull up.
Qualified Sensors: 0–2k
potentiometer, RTD (1k Nickel
[Johnson Controls sensor], 1k
Platinum, and A99B Silicon
Temperature Sensor) NTC Sensor
(10k Type L, 10k JCI Type II,
2.252k Type II).
See Guideline A in Table 7.
UI-#
Binary Input - Dry Contact
Maintained Mode
1 second minimum pulse width
Internal 12 V, 15k Ohms pull up.
See Guideline A in Table 7.
UNIVERSAL
(Inputs)
UI-C#
Universal Input Common for all
Universal input terminals
Note: All Universal UI-C#
terminals share a common,
which is isolated from all
other commons.
Same as (Universal) UI-#.
F4-SNC Installation Guide8

Table 6: Terminal wiring
Terminal block label Terminal labels Function, ratings, and
requirements
Determine wire size and
maximum cable length
Binary Input - Dry Contact
Maintained Mode
0.01 second min. pulse width.
Internal 17 V, 3k Ohms pull up.
BI-# Binary Input - Pulse Counter/
Accumulator Mode
0.01 second min. pulse width.
(50 Hz at 50% duty cycle).
Internal 17 V, 3k Ohms pull up.
BINARY
(Inputs)
BI-C# Binary Input Common for all
Binary Input terminals
See Guideline A in Table 7.
Analog Output - Voltage Mode
(0–10 VDC)
10 VDC maximum output
voltage.
10 mA maximum output current.
Requires an external load of
1,000 Ohms or more.
Note: The AO operates
in Voltage Mode when
connected to devices
with impedances greater
than 1,000 Ohms. Devices
that drop below 1,000
Ohms may not operate as
intended for Voltage Mode
applications.
See Guideline C in Table 7.
AO-#
Analog Output - Current Mode
(4–20 mA)
Requires an external load
between 0–300 Ohms.
Note: The AO operates
in Current Mode when
connected to devices with
impedances less than 300
Ohms. Devices that exceed
Ohm may not operate as
intended for Current Mode
applications.
See Guideline B in Table 7.
ANALOG
(Outputs)
AO-C#
Analog Output Signal Common
for all Analog OUT terminals
Note: All Analog AO-C#
terminals share a common,
which is isolated from all
other commons.
Same as (Analog) AO-#.
F4-SNC Installation Guide 9

Table 6: Terminal wiring
Terminal block label Terminal labels Function, ratings, and
requirements
Determine wire size and
maximum cable length
BO-#
Binary Output - 24 VAC Triac
(External Power)
Connects BO-# to BO-C# when
activated.
External Power Source:
30 VAC maximum output voltage.
0.5 A maximum output current.
1.3 A at 25% duty cycle.
Maximum 6 cycles/hour with
M9220-BGx-3.
40 mA minimum load current.
BINARY
(outputs)
BO-C#
Binary Output Common (for
BO-# terminal)
Note: Each Binary Output
common terminal is
isolated from all other
commons, including other
Binary Output commons.
See Guideline C in Table 7.
Analog Output - Voltage Mode
(0–10 VDC)
10 VDC maximum output
voltage.
10 mA maximum output current.
Requires an external load of 1000
Ohms or more.
See Guideline A in Table 7.
CO-#
Binary Output 24 VAC Triac
(External Power Source only)
Connects CO-# to CO-C# when
activated.
External Power Source:
30 VAC maximum voltage to
load.
0.5 A maximum output current.
1.3 A at 25% duty cycle.
Maximum 6 cycles/hour with
M9220-BGx-3.
40 mA minimum load current.
See Guideline C in Table 7.
CONFIGURABLE
(Outputs)
CO-C#
Analog Output Signal
Common: All Configurable
Outputs defined as Analog
Outputs share a common,
which is isolated from all other
commons except the Binary
Input common.
Binary Output Signal Common:
All Configurable Outputs defined
as Binary Outputs are isolated
from all other commons,
including other Configurable
Output commons.
Same as (Configurable) CO-#.
The following table defines cable length guidelines for the various wire sizes that can be used for input and output
wiring.
F4-SNC Installation Guide10

Table 7: Cable length guidelines for recommended wire sizes
Guideline Wire size/gauge and type Maximum cable length and
type Assumptions
1.0 mm (18 AWG) stranded copper 457 m (1,500 ft) twisted wire
0.8 mm (20 AWG) stranded copper 297 m (975 ft) twisted wire
0.6 mm (22 AWG) stranded copper 183 m (600 ft) twisted wire
A
0.5 mm (24 AWG) stranded copper 107 m (350 ft) twisted wire
100 mV maximum voltage drop
Depending on the cable length
and the connected input or
output device, you may have
to define an offset in the setup
software for the input or output
point.
1.0 mm (18 AWG) stranded copper 229 m (750 ft) twisted wire
0.8 mm (20 AWG) stranded copper 137 m (450 ft) twisted wire
0.6 mm (22 AWG) stranded copper 91 m (300 ft) twisted wire
B
0.5 mm (24 AWG) stranded copper 61 m (200 ft) twisted wire
100 mV maximum voltage drop
Depending on the cable length
and the connected input or
output device, you may have
to define an offset in the setup
software for the input or output
point.
CSee Figure 8 to select wire size/gauge. Use
stranded copper wire.
See Figure 8 to determine cable
length. Use twisted wire cable. N/A
Maximum cable length versus load current
In most cases inputs/outputs with cables less than 30 m (100 ft) do not require an offset in the software setup. Cable
runs over 30 m (100 ft) may require an offset in the input/output software setup. Use Figure 8 to estimate the maximum
cable length relative to the wire size and the load current (in mA) when wiring inputs and outputs.
Figure 8: Maximum wire length by current and wire size
Communications Bus and supply terminal blocks, functions, ratings, requirements,
and cables
Table 8: Communications Bus and supply terminal blocks, functions, ratings, requirements, and cables
Terminal block/
port label
Terminal
labels Function, electrical ratings/requirements Recommended cable type
- (03)
+ (04) FC Bus Communications
COM (02) Signal Reference (Common) for bus communications
FC BUS
SHLD (01) Isolated terminal (optional shield drain connection)
0.6 mm (22 AWG) stranded, 3-
wire twisted, shielded cable
recommended
FC BUS
(port) FC Bus
RJ12 6-Position Modular Connector provides:
• FC Bus Communications
• FC Bus Signal References and 15 VDC Common
• 15 VDC Power for Wireless Commissioning
• Converter or ZFR1811 Wireless Router
Wireless Commissioning Converter
retractable cable or 24 AWG 3-pair
CAT 3 Cable <30.5 m (100 ft)
F4-SNC Installation Guide 11

Table 8: Communications Bus and supply terminal blocks, functions, ratings, requirements, and cables
Terminal block/
port label
Terminal
labels Function, electrical ratings/requirements Recommended cable type
- (03)
+ (04) SA Bus Communications
COM (02) SA Bus Signal Reference and 15 VDC Common
SA BUS
SA PWR (01) 15 VDC Supply Power for Devices on the SA Bus (Maximum total
current draw for SA Bus is 240 mA.)
0.6 mm (22 AWG) stranded, 4-
wire twisted, shielded cable
recommended
Note: The + and - wires are
one twisted pair and the COM
and SA PWR are the second
twisted pair of wires.
SA BUS
(Port)
6-Position Modular Connector provides:
• SA Bus Communications
• SA Bus Signal References and 15 VDC Common
• 15 VDC Power for devices on the SA Bus and
• Wireless Commissioning Converter
24 AWG 3-pair CAT 3 Cable <30.5 m
(100 ft)
HOT 24 VAC Power Supply - Hot
Supplies 20-30 VAC (Normal 24 VAC)
24~
COM 24 VAC Power Supply Common (Isolated from all other
Common terminals on controller)
0.8 mm to 1.5 mm (20 to 16 AWG) 2-
wire
Note:
• See Table 7 to determine wire size and cable
lengths for cables other than the recommended
cables.
FC Bus and SA Bus and supply power
wiring guidelines
Table 8 provides information about the functions, ratings,
and requirements for the SNC communication bus
and supply power terminals, and guidelines for wire
sizes, cable types, and cable lengths when wiring the
communication buses and supply power.
In addition to the guidelines in Table 8, observe these
guidelines when wiring the FC Bus and SA Bus supply
power:
• Run all low-voltage wiring and cables separate from
high-voltage wiring.
• Use twisted, insulated, stranded copper wire for all FC
and SA Bus cables, regardless of wire size.
• Shielded cable is strongly recommended for all FC and
SA Bus cables.
Termination diagrams
A set of Johnson Controls termination diagrams provides
details for wiring inputs and outputs to the controllers.
See the figures in this section for the applicable
termination diagrams.
F4-SNC Installation Guide12

Table 9: Termination diagrams
Type of field device Type of input/
output Termination diagrams
Temperature Sensor UI
Voltage Input - External Source UI
Voltage Input - Internal Source UI
Voltage Input (self-powered) UI
Current Input - External Source
(isolated) UI
Current Input - Internal Source
(2-wire) UI
F4-SNC Installation Guide 13

Table 9: Termination diagrams
Type of field device Type of input/
output Termination diagrams
Current Input - Internal Source
(3-wire) UI
Current Input - External Source
(in loop) UI
Feedback from EPP-1000 UI
Dry Contact (binary input) UI or BI
0–10 VDC Output to Actuator
(external source) CO or AO
0–10 VDC Output to Actuator
(internal source) CO or AO
Current Output AO
F4-SNC Installation Guide14

Table 9: Termination diagrams
Type of field device Type of input/
output Termination diagrams
Analog Output (current) AO
24 VAC Triac output (switch high,
internally sourced, Triac) BO or CO
24 VAC Triac output (switch low,
external source) BO or CO
Incremental control to actuator
(switch high, internally sourced,
Triac)
BO
Incremental control to actuator
(switch low, internally sourced,
Triac)
BO
Network Stat with Phone Jack
(Fixed Address = 199) SA Bus
F4-SNC Installation Guide 15

Table 9: Termination diagrams
Type of field device Type of input/
output Termination diagrams
Network Stat with Terminals
Addressable SA Bus
NS8000 series sensors SA Bus
Network Stat with Terminals
(Fixed Address = 199) SA Bus
Input/Output wiring validation
The SNC includes integral wiring validation for onboard
Inputs/Outputs with a default state application. The SNC
controllers ship with a default state that can assist in
validating the wiring of the input and output terminals
prior to download of an application file. No special actions
need to be taken to make use of this feature. Apply power
to the SNC controller and connect to the device with
a Site Management Portal UI to view the integral I/O
points in the controller. The points are viewable under
the Local Hardware folder of the device and are named
according to the I/O they represent, for example UI-1. It
is possible to upload the default state application with the
Site Configuration Tool (SCT), as needed.
The default state creates I/O points for all connections
on the input and output terminals. It assumes all
Universal Inputs (UIs) are Nickel temperature sensors. All
Configurable Outputs (COs) are treated as Binary Outputs
(BOs) with an initial value of 0. The default state also takes
input from a Network Sensor at address 199. If there is
no connected Network Sensor, the startup of this default
state is delayed by 30 seconds as the controller attempts
to establish connection with the sensor.For more details
about the default state workflow, refer to information on
the FAN-410.
Note: The SNC is not currently supported at MAP
Gateway release 5.1.
Setting the EOL switch
The network devices at the end of an FC Bus segment
must be set as network terminated devices. The SNC
has one red EOL switch labeled FC EOL for the FC Bus
connection that sets the engine as a network terminated
device on the bus.
To set a SNC as an FC Bus terminated device, position the
switch on the EOL switch to the ON position as shown in
Figure 9.
Figure 9: FC Bus EOL switch: ON (Up) position
F4-SNC Installation Guide16

Note: The SNC is shipped with the EOL switch in the
initial factory position, ON (up) position as shown in
Figure 9. If the SNC is not a terminated device on the
FC Bus, reposition the EOL switch to the Off (down)
position.
Set the EOL switches appropriately for the FC Bus.
For the RS-485 connection, set the EOL termination to
ON (or install an EOL terminator) for the two devices
located at either end of each bus segment on an RS-485
Bus. Set the EOL switches to off (or do not install an EOL
terminator) for all other devices on the bus segment on
an RS-485 Bus.
Powering on the SNC
Apply power to the SNC. The device requires
approximately three minutes to start up and become
operational. See LED test sequence at startup.
Startup is complete and the SNC is operational after the
HEARTBEAT LED flashes blue/purple at 1 Hz and the red
FAULT LED is off.
Disconnecting power from the SNC
Disconnect power from the SNC by removing the gray 2-
pin terminal block from the 24 V~ power terminal port on
the SNC.
When you disconnect or lose supply power from the
SNC, the SNC becomes non-operational when the power
management settings expire. The blue HEARTBEAT
LEDremains on, and the super capacitor continues to
power the SNC for approximately 30 seconds so that
volatile data can be backed up in nonvolatile memory.
The HEARTBEAT LED goes off when the data backup
completes.
Important: The behavior of the super capacitor
is different from backup batteries that network
engines have used in the past. For example, the
capacitor requires time to recharge after each power
cycle. The unit is not designed for frequent power
cycles over a short period of time, such as three or
four power cycles in one hour. In this scenario, the
capacitor can deplete enough so that it no longer
functions. A fully depleted capacitor can take up to
90 minutes to recharge after the SNC is plugged into
its power source.
Rotary switch dials
The SNC has 3 rotary switch dials labeled Controller
Number for setting the controller number which can be
numbered from 000 to 999. The switches are shipped
from the factory set to 000. You can use them to set a
decimal number from 000 to 999 as a unique identifier for
each SNC.
Setting the controller number
About this task:
The controller number is set using three rotary switches
and may be numbered from 000 to 999. The numbers are
ordered from left to right, most significant bit (MSB) to
least significant bit (LSB) when the controller is oriented
as shown in . In Figure 10 the switches are set to 1 2 3.
If you change the controller number, refresh the SMP
Hardware tab to see the change.
Figure 10: Rotary switch controller number
Troubleshooting
LED status indicators
LEDs on the front panel of the SNC indicate its functional
state. For a comprehensive list of LED functional
information, see Table 10.
LED test sequence at startup
During startup, the SNC automatically initiates a self-test
to verify correct operation of the unit. When you connect
supply power, the following LED lighting sequence occurs:
• The HEARTBEAT LED flashes blue/purple when the SNC
starts.
• The FAULT LED is solid red for approximately 30
seconds, then turns off.
• The USB-1|2 LED flashes green when a supported
device is connected to either of the USB ports. The
LED turns solid red when an unsupported device is
connected. The LED is off if no device is connected.
SNC LED indication table
Table 10 describes each LED on the device. The normal states are in bold. A flicker has a fast blink rate faster than one
second and a flash has a much slower blink rate of one second.
F4-SNC Installation Guide 17

Table 10: SNC LED designations, normal statuses, descriptions, and other conditions
LED name Color State Description
Flashing blue
and purple
1 blink per second (1 Hz) = Normal operating system and all monitored
processes start and the device is running
On blue Power is supplied by 24 VAC, but controller is non-operational
Medium flicker,
purple and blue 2 blinks per second (2 Hz) = SNC starting up
Fast flicker,
purple and blue 5 blinks per second (5 Hz) = SNC shutting down
HEARTBEAT Multi-color: blue
or purple
Off No power
Off No faults and normal operation
FAULT Red On
Device fault or no application loaded. Diagnostics are running or fault
conditions are detected. For example, excessive memory or flash usage, or a
high CPU/PWB temperature.
Flashing 1 blink per second (1 Hz) = indicates communication activity
SA BUS Green On Devices have been defined but none are communicating (network engine
transmitting only)
Flashing 1 blink per second (1 Hz) = indicates communication activity
Off No devices are communicating or no controllers have been configured to
work with this busFC BUS Green
On Controllers have been defined but none are communicating (network
engine transmitting only)
Flickering Data is transferring on the Ethernet connection
ETH-1 and ETH-2 Green Off No communications
Flashing Flash green = 1 blink per second (1 Hz), an approved device or devices are
connected and communicating correctly to either USB-1|2
On
Solid red = an unapproved device is connected to USB 1 and/or USB 2. In this
case a user needs to sequentially remove each device until the LED flashes
green or the LED is turned off.
Note: Only approved USB adapters that have been tested and
qualified function with the SNC. Non-qualified adapters do not
function with the SNC.
USB-1|2 Green or Red
Off No USB device is connected
On On Steady = end-of-line termination is enabled for the Field Bus connection
EOL Yellow Off Off Steady = indicates the end of line termination network is disabled
F4-SNC Installation Guide18

Reset button
The SNC features a recessed Reset button that is located
directly above the LEDs and to the left of the Recovery
button. To force an immediate restart of the SNC engine
and a reset of the processor, press and hold down the
Reset button for at least four seconds with an extended
paper clip or mini screwdriver. This action is otherwise
known as a hard reset or processor reset. During the
reset, the SNC's archive database and any data the SNC
has collected are lost. The data includes all historical
information, including alarm, trend, and audit trail
data. If you need to reset the SNC but retain the archive
and stored historical data, you can either press and
immediately release the reset button, or issue a Reset
Device command from the user interface. This type of
reset is known as a soft reset.
Note: Press the reset button only if the SNC fails to
respond and users cannot access it. Do not press the
reset button unless you have tried other means to
fix the problem.
Recovery button
The SNC features a recessed Recovery button that is
located above the LEDs and to the right of the Reset
button. Use the Recovery button to restore device
functionality. To place the SNC into recovery mode, press
and immediately release the Recovery button with an
extended paper clip or mini screwdriver. Use the Recovery
operation under these conditions:
• the current password is unknown
• the device is rebooting continuously
• the device is unresponsive or is in a frozen state
• the device fails to take a code download from SCT
Important: If you are unsure about whether to use
the Recovery operation, contact Johnson Controls
technical support.
When you press the Recovery button, the action that
takes place depends on whether this is the first time or
a subsequent time you pressed the button. The actions
taken are as follows:
•First press (odd-numbered): The SNC resets and
restores the factory default settings on the active
partition.
•Second press (even-numbered): The SNC resets
and makes the opposite partition the currently active
partition with the factory default settings. Any staged
configuration files are lost. If the SNC has never been
imaged with a release other than the shipped factory
release, then both partitions (active and inactive) are
now at the same release. Once the SNC is imaged in
the field with a release other than the factory release,
the active and inactive partitions are at different
releases. At this point, it is your responsibility to verify
the SNC's active partition is at the correct release. If it
is not, you need to download the SNC with the correct
code from SCT.
This process repeats the next time the Recovery button
is pressed with the exception of each time an SCT code
download is performed, which resets the Recovery button
back to the default setting.
The differences between the two states are further
described in Partition example.
Notes:
• To determine which partition is currently active, open
the FX SMP UI in Expert mode and locate the Update
object of the SNC under All Items - Expert tab. The
Active System Partition attribute is visible under
the Focus window of the Update object as either A
(Partition 0) or B (Partition 1).
• After you press the Recovery button, allow time for
the SNC to restart before you press the button again.
Pressing the button twice in fast sequence equates to
pressing the button only once.
• The firmware version in the inactive partition may be
older than the version in the active partition, and may,
in fact, lack security enhancements that are present in
the newer, active partition.
• If the system partition to which you are switching is
corrupt, the operating system loader does not switch to
the defective partition, but instead keeps the currently
active partition in place.
F4-SNC Installation Guide 19

Partition example
Table 11: Partition example using Recovery button and SCT Code Download
Partition
User Action A B SNE Release per Partition
Verify currently
active partition Active Inactive Partitions A and B have Rel. 10.1.0.3976
Press button 1st
time Active Inactive Partitions A and B have Rel. 10.1.0.3976
Press button 2nd
time Inactive Active Partitions A and B have Rel. 10.1.0.3976
Press button 3rd
time Inactive Active Partitions A and B have Rel. 10.1.0.3976
Press button 4th
time Active Inactive Partitions A and B have Rel. 10.1.0.3976
Press button 5th
time Active Inactive Partitions A and B have Rel. 10.1.0.3976
Perform SNC code
download Rel.
11.0.0.7212 with SCT.
Inactive Active Partition B has Rel. 11.0.0.7212
Partition A has Rel. 10.1.0.3976
Press button 6th
time Inactive Active Partition B has Rel. 11.0.0.7212
Partition A has Rel. 10.1.0.3976
Perform SNC code
download Rel.
11.0.0.7212 with SCT.
Active Inactive Partition A has Rel. 11.0.0.7212
Partition B has Rel. 11.0.0.7212
Press button 7th
time Active Inactive Partition A has Rel. 11.0.0.7212
Partition B has Rel. 11.0.0.7212
Wiring considerations and guidelines
Table 12: Ethernet network rules
Category Allowed maximums and rules
General Star topology with network switches
2,000 m (6,600 ft) for plastic or glass fiber optic with external adapter
Line length and type 1000 BaseT: 100 m (330 ft) CAT5E cable
100 BaseT: 100 m (330 ft) CAT5 cable
10 BaseT: 100 m (330 ft) CAT5 cable
Terminations For 1000/100/10 BaseT, no line terminators allowed.
Table 13: FC Bus rules for MS/TP devices
Category Allowed maximums and rules
General
One FC Bus with up to 50 MS/TP devices for SNC25151-0 and SNC16121-0 and up to 4 MS/TP
devices for the SNC25151-0x/x and SNC16121-04.
Note: An FC port on a SNC can connect to only one bus segment on an FC Bus.
Only a daisy-chain topology is allowed (no Star or T topology configurations).
One FC Bus Supports up to 50 MS/TP controllers on a single FC Bus segment for the SNC25151-0
or SNC16121-0.
Number of devices One FC Bus Supports up to 4 MS/TP controllers on a single FC Bus segment. for the SNC25151-0x/
x or SNC16121-04.
F4-SNC Installation Guide20