Johnson Controls METASYS NU-XBN101-0 User manual

Metasys Network Technical Manual 636
Point Multiplex Modules Section
Technical Bulletin
Issue Date 0693
© 1993 Johnson Controls, Inc. 1
Order No. 636-027
Introduction Page 3
●
Description 3
●
Capabilities 5
●
Specification 6
Engineering 7
●
Theory of Operation 7
●
Design Considerations 9
●
XBN Switches 11
●
Wiring Details 12
●
Software Setup 27
Commissioning Procedures 29
●
Overview 29
●
Switch Settings 29
●
Power Up 32
Troubleshooting Procedures 33
●
Self-Diagnostics 33
●
Field Checks 33
●
Ordering Information 35
Multiplex Binary

2 Point Multiplex Modules—Multiplex Binary

Point Multiplex Modules—Multiplex Binary 3
Introduction
The Multiplex Binary (XBN) is a module that interfaces points to the
system and resides in the Network Control Unit (NCU) or Network
Expansion Unit (NEU). It monitors up to 32 binary inputs (voltage, dry
contact, or pulse), then reports changes in their states to the NCU for
processing. LEDs on the module face display the status for each
corresponding input.
Figure 1: Multiplex Binary
Description
PHOTO

4 Point Multiplex Modules—Multiplex Binary
The XBN interfaces a high concentration of binary input points to the
NCU or NEU. The inputs may be any combination of these points: dry
contact, up to 10 Hz frequency, and up to 120 VAC or VDC.
When residing in or remote to an NCU, the XBN serves to increase the
point capacity of the NCU.
If the points are clustered at a distant location, the XBN additionally
provides an economical way to connect them to the NCU

over the
N2 Bus

without having to hardwire each contact separately to the NCU.
Typically, the XBN monitors the status of 2-position devices such as fans,
pumps, or security panels. Voltage input from a starter or pilot device can
also indicate that the equipment has changed state.
In addition, the XBN can detect pulses from flow meters, electric utility
meters, or other pulse output devices whose frequency is 10 Hz or less.
The pulses are collected in the XBN’s accumulator, then transmitted to the
Network Control Module where they are converted into readable analog
values.
The diagram below illustrates a configuration using two XBNs: the first
XBN oversees HVAC-related fans and pumps near a building entrance.
The data is transmitted over an N2 Bus to the NCU in the main equipment
room. The second XBN is installed directly in the NCU, monitoring a
variety of binary inputs in the equipment room itself.
N1 LAN
Operator
Workstation
NEU
w/XBN Inside
N1 LAN
Equipment Room
NCU
w/XBN Inside
with2xbn
Building
Entrance
Figure 2: Typical Application with Two XBNs
Purpose
Application

Point Multiplex Modules—Multiplex Binary 5
Table 1: Capabilities
Capabilities
Capability Description Purpose
Modular Packaging XBN electronics are integrated with system circuitry
(eliminating the need for separate boxes for wires,
transducers, etc.) and are housed in durable cases.
Modules plug in and lock into position.
Simple to install and service; casing prevents
physical and ESD damage in addition to shielding
electronics from induced noise.
32 Binary Inputs DC, AC, Dry Contact, and Pulse Interfaces a high concentration of binary devices;
flexibility to retrofit existing devices.
LED Indicators 32 Binary Inputs (software-configured: light ON =
either closed contact/voltage absent), N2 Transmit,
N2 Receive, Power, and Error (sanity circuit reset,
check sum, RAM test result)
Determine module status by visual inspection.
Enhanced Input Circuitry Each input is balanced differentially, with a high
input impedance (significantly reducing amperage)
and high level of isolation from noise and
transients. Inputs withstand 120 VAC RMS of
normal mode voltage.
The XBN withstands high levels of noise, especially
common mode noise. Enables mixed input and
output lines through a conduit, when allowed by
local electrical codes.
Point Status Change
Reports The XBN latches and holds any valid data changed
from an input point; further data changes are
ignored until the first-detected change has been
reported to, and acknowledged from, the NCM.
Report COS for alarm analysis or program
triggering, and to notify operator(s).
Disable COS Reporting Suppresses COS, reporting capabilities on a per
input basis. While COS reporting is disabled, the
NCM can still request point status without re-
enabling the COS report functions.
Prevent constant COS reports from specified points
(e.g. fluttering airflow switch).
Debounce Filter Programs the XBN to ignore transient or intermittent
changes by requiring consecutive identical input
data before determining the current state.
Helps prevent false alarms or erroneous counts in
accumulator points.
Accumulator (Pulse
Applications) For each status input, detects and totals transitions
for pulses of less than or equal to 10 Hz (each
pulse yields two transitions). When requested by
the NCM, the Accumulator releases the number of
valid signal transitions (up to 65,535 before rolling
over).
Permit monitoring of devices that transmit
frequency signals.

6 Point Multiplex Modules—Multiplex Binary
Table 2: Specifications
Product Description
Code Name Multiplex Binary (NU-XBN101-0)
Microprocessor Intel 80C51
Memory 8K by 8-bit Static RAM
8K by 8-bit E2PROM
Binary Inputs 32 (contact, voltage present/absent, and low frequency pulses)
Maximum Input Voltage 120 VDC or 120 VAC RMS 50/60 Hz
Maximum Pulse Input
Frequency 10 Hz or less (at 10 Hz, 12 mS < positive pulse
width < 52 mS; and Debounce Filter set to 2)
Input Types DC-Low Thresh: 3 V, Hi Thresh: 8 V
AC - Low Thresh: 2V, Hi Thresh: 18 V
Dry Contact - Low Thresh: 100 K ohms, Hi Thresh: 800K ohms
Pulse—(0-10 Hz)
Minimum Output Load 10 mA at 5 VDC
Source Power Power is from PWR in the NCU/NEU
Operating Temperature 32°to 122°F (0°to 50°C)
Storage Temperature -40°to 158°F (-40°to 70°C)
Operating Humidity 10% to 90% RH
Storage Humidity 5% to 95% RH
Dimensions and Weight 14 in. H x 1.5 in. W x 6 in. D (355 x 36 x 152mm); 2 lbs 11 oz (1.13 kg)
Agency Compliance FCC Part 15, Subpart J, Class A
UL916
CSA C22.2 No. 205
Agency Listing UL Listed and CSA Certified as part of the MetasysNetwork
Specifications

Point Multiplex Modules—Multiplex Binary 7
Engineering
The figure below illustrates the XBN’s general components and their
functions.
Field input ①is routed either through an IUN function module or directly
into the base frame, depending on the XBN’s slot position.
V/C
IUN FM
Input
Circuit
Address
Debounce
Filter Software
EOL
Microprocessor
N2
Circuit
LEDs
N2 LEDs
or
3
2
4
6
5
1
8
7
Signal
XBN
Figure 3: XBN Block Diagram
Thirty-two identical binary input circuits ②monitor input signals (dry
contact, DC voltage, AC voltage, or frequencies of 10 Hz or less)
changing from logical status 0 (voltage absent, contact open) to 1 (voltage
present, contact closed) under these conditions:
Table 3: Input Signals
Sensed Input Logical 0 Logical 1
Contact > 800K ohms < 100K ohms
VDC <3 VDC > 8 VDC to limit of 120
VAC <2 VAC > 18 VAC to limit of 120
Frequency <10 Hz
12 mS < Pos. Pulse < 52 mS at 10 Hz
Debounce count set to 2
Point defined as accumulator
The user sets a switch for each input ③to select which type of signal the
input senses: voltage or contact.
●If the V/C switch is incorrectly set to voltage, no contact changes-of-
state can be sensed by the circuit.
●If the V/C switch is incorrectly set to contact, voltage differentials
greater than -12 (e.g., -10) produce a logical 1; voltages less than -12
Theory of
Operation

8 Point Multiplex Modules—Multiplex Binary
(e.g., -14) produce a logical 0. For large AC voltages, this may not
have consequences, but low voltage levels will result in errors.
Address switches ④provide a means to identify the module along the N2
Bus. An End-of-Line (EOL) switch ⑤must also be positioned correctly
for the N2.
Each input is protected to withstand all types of short circuits (input to
input, across an input, input to other potentials) without damage, although
operation would be temporarily unreliable. Input circuitry also protects
against transient overvoltages of up to 1000 volts peak, with current
tolerance to ESD static spikes protected to 6000 volts.
Input changes are filtered in software by a debounce filter ⑥downloaded
into memory.
LEDs ⑦indicate the state of the respective input as received by the
microprocessor after debounce filtering. The state of the input
representing LED On is software programmable (either contact
closed/voltage present or contact open/voltage absent).
The microprocessor outputs signals to the N2 communications circuitry ⑧
on the NCU/NEU backplane. Additional LEDs indicate N2 transmit and
receive signals, as well as power and sanity circuit/firmware errors.

Point Multiplex Modules—Multiplex Binary 9
The XBN monitors up to 32 binary inputs. As a module that fits into
specific slots on the NCU/NEU base frame, its environmental
requirements are identical to those of the NCU/NEU and may be
referenced in that technical bulletin. Power is supplied by an associated,
and separately ordered, Power Supply Module.
The figure below illustrates in which slots the module may be installed
(into any base frame’s slot except the number 3 slot of a 5-slot base
frame).
5-slot 2-slot
1-slot5-slot 2-slot
xbn2
Figure 4: Mounting Options for the XBN
When installing an XBN into a slot normally occupied by a DCM
(Slots 1 and 5 of a 5-slot, Slot 1 of a 2-slot), an IUN Function Module is
necessary to transmit signals from the first 16 terminal blocks of the
NCU/NEU to the XBN. Each IUN transmits two independent signals,
requiring a total of eight IUNs. Inputs 17-32 (see Figure 19 for input
locations) terminate on the bottom 16 terminal blocks and do not require
Design
Considerations
Mounting
Darkened slots indicate
Point Multiplex Module
location options.
When placed in slots
normally occupied by
DCMs, Point Multiplex
Modules require IUN
FMs (also darkened).

10 Point Multiplex Modules—Multiplex Binary
IUNs to transmit signals to the XBN. The presence of the IUN FM does
not change or expand the range of signals processed by the XBN.
All configurations of the XBN in relation to other modules in the
NCU/NEU panel are compatible, provided that the modules are properly
located and the points correctly defined in the software.
Wiring both states of a Form C input requires two binary input terminals,
as illustrated in Figure 5.
Note: Form C inputs must connect to adjacent screw terminal blocks,
starting at an odd-numbered block (i.e., 1 and 2, 27 and 28;
not 2 and 3, etc.).
Using all Form C inputs would reduce the point monitoring
capacity from 32 to 16.
xbn3
Binary
Device
GND
GND
-
+
-
+
-
-
+
+
(5)
(6)
Base
Frame
Figure 5: One Form C Input Terminating in Two Binary Inputs
To suppress nuisance signals from a noisy binary input, change the
Debounce Filter to a value higher than the default of 2 (24 milliseconds);
e.g., to 3, which yields 36 milliseconds.
An exception to this is when the input is a 0 to 10 Hz pulse input. In this
case, the Debounce filter must be 24 milliseconds or less, and shields or
other methods must be used to reduce the susceptibility of the lines to
induced noise. See Debounce Filter under the Binary Input Object
Technical Bulletin.
Form C Inputs
Binary Inputs In
Noisy Environments

Point Multiplex Modules—Multiplex Binary 11
Set the following switches on the XBN. Although the switches may be set
either before or after installing the module, the N2 address switch must be
set before turning power On (to register the physical address switch in
memory). A change in the N2 address switches requires cycling power to
the XBN.
The N2 Address Switch sets the node address of the XBN. The switch
contains eight binary settings, resulting in an address range of 0-255. Set
the switches corresponding to the module’s software-defined address.
Two devices within each N2 Network must be designated as End-of-Line
(EOL). For details regarding what constitutes EOL, refer to the N2
Communications Bus Technical Bulletin. Set the XBN module as one
EOL device by sliding its switch up to “In.”
The XBN has four contact/voltage blocks containing eight switches. The
switches are numbered 1-32 with each switch defining a corresponding
field input as either a contact input or voltage input (frequency inputs are
characterized by their source as either contact or voltage). Set each switch
according to the type of signal the addressed point should receive. The
switch set to “V” reads voltage; set to “C” reads contact.
EOL Switch
Address Switches
Voltage/Contact Switches
xbn4
Figure 6: Location of XBN Switches
XBN Switches
N2 Address Switch
End-of-Line Switch
for N2 Bus
Voltage/Contact
Switch

12 Point Multiplex Modules—Multiplex Binary
Since the XBN and its associated power supply are both in modular form,
the act of installing the module onto a base frame also makes all of the
wiring connections for it. Only the field and communication wires need to
be terminated.
The XBN withstands high levels of transient-voltage noise, which makes it
possible to simply use individual, small gauge (14-28 AWG) wire and still
yield excellent results. Apply the following guidelines when wiring
through conduits or wire channels to the XBN:
1. Installations can typically use individual wires (stranded or solid),
depending on local codes.
2. If an installation is expected to be in an extremely noisy environment
(e.g., TV/radio stations or radar installations), a twisted pair cable
provides greater noise immunity, leading to higher reliability.
Shielding reduces noise even more, but it is not considered a necessity.
This is true for all types of connections: voltage input or contact input.
3. Output wires may run with input wires (provided electrical codes are
met) within the same conduit or wire channel.
4. The wire/cable insulation must meet code requirements.
For details about connecting the XBN to the N2 Bus, refer to the N2
Communications Bus Technical Bulletin in this manual.
On the base frame, the field connections are provided in the form of screw
terminal blocks. Each terminal location can handle a maximum size of
one 14 AWG or two 18 AWG wires (to daisy chain), or a minimum size of
28 AWG wire.
Each field connection may require three screw terminals, two for signal
and one for an optional shield.
Contact Inputs
The contact inputs can be wired without concern for polarity, although
consistency in wiring (+) and (-) lines is recommended for both service
and safety purposes.
Wiring Details
Cabling to the
NCU/NEU
Connecting the N2
Communications
Line
Field Wiring

Point Multiplex Modules—Multiplex Binary 13
If the (-) line is daisy chained as a single common (Figure 7), consistency
between (-) and (+) wires must be maintained. Also, 18 AWG (maximum)
wire must be used where the two (-) wires insert under a single terminal.
xbn5
Binary
Input 1
XM
Termination
Board
+
_
+
_
+
_
(+)
(-)
(+)
(+)
Binary
Input 2
Binary
Input 3
18 AWG
or smaller
Figure 7: Wiring Contacts Using a Single Common (Daisy Chained)
Use the paired-wire technique (Figure 8), and not the daisy chained
scheme, when connecting to various, widely spaced devices, since a
single, widely spaced common may create a loop (antenna) effect and
induce significant transient noise onto the system.
xbn6
Binary
Input 1
XM
Termination
Board
+
_
+
_
+
_
(+)
(-)
(+)
(+)
Binary
Input 2
Binary
Input 3
(-)
(-)
Figure 8: Wiring Contacts Using Paired Wires

14 Point Multiplex Modules—Multiplex Binary
Voltage Inputs, Line Voltage AC
Line-voltage AC inputs (>30 VAC RMS) can also be wired without
concern for polarity; again, consistency is recommended for both service
and safety purposes (Figure 9):
xbn7
M
M
M
=Motor or
Pilot Light
Hot Neutral
120 VAC
Binary
Input 1
Binary
Input 2
Hot Neutral
XM
Termination
Board
+
_
+
_
Figure 9: Wiring Line-Voltage AC Using Paired Wires

Point Multiplex Modules—Multiplex Binary 15
Voltage Inputs, DC and Low-Voltage AC
Terminate all DC and low AC (<30 VAC RMS) voltages in the manner
illustrated in Figure 10. Wire the:
●positive voltage to the most internal (+) terminal
●negative voltage to the middle (-) terminal
●shields, if used, to the ground terminal
-+
-+-
-
GND
GND GND
++
-
Input 2
Input 1
Input 2
Input 1
-
+
+
Input 2
Input 1
xbn8
Figure 10: XBN Input Terminal Designations for VDC and Low AC

16 Point Multiplex Modules—Multiplex Binary
Six kinds of applications that input to the XBN are described on the
following pages. Three common applications connect to the XBN without
alteration to the circuit:
●devices wired across a load
●devices wired across non-grounded (dry) contacts
●devices in contact mode with open inputs and one side grounded
Three other applications require a small modification before connecting to
the function module because unloaded XBN voltage inputs are sensitive to
noise, especially when one of the input lines is earth grounded. This noise
results in faulty readings.
●unpowered triac or SCR contact
●high powered (>1 amp) non-wiping contact
●neon lamp applications
Wiring methods for each of the six applications are shown on the
following pages.
Field Wiring
Applications

Point Multiplex Modules—Multiplex Binary 17
Binary Input Wired Across the Load
A binary input wired across the load (Figure 11) is a typical wiring
configuration and requires no alteration to the circuit. Set the XBN mode
switch to voltage. Examples of these loads include:
•fan motors
•pumps
•lights
•compressors
HN
120 V
Control
Switch
M
xbn9
Figure 11: Wiring Across the Load
For applications normally wired across the load, make sure you don’t wire
across the control switch (Figure 12).
HN
120 V
Control
Switch
M
xbn10
Figure 12: Incorrect Wiring Method (Across Control Switch)

18 Point Multiplex Modules—Multiplex Binary
Binary Input Wired Across the Dry Auxiliary Contacts
A binary input wired across the dry auxiliary contacts (Figure 13) is a
second typical wiring configuration. It also requires no alteration to the
circuit. Set the XBN mode switch to contact. Examples of these loads
include:
•starters for motors or pumps
•retrofits where control contacts are already in place
•high-voltage devices controlled by auxiliary contacts
H N
120 V
Control
Switch
H
OLS
A
Coil
O
Device Under Control
Auxiliary
Contacts
xbn11
Figure 13: Wiring Across Dry Contacts

Point Multiplex Modules—Multiplex Binary 19
Open Inputs with One Side Grounded
If an open input device is wired to ground on one side of the circuit
(Figure 14), set the XBN switch to contact mode to provide accurate
readings.
xbn12
Figure 14: With Open Binary Inputs and One Side Grounded,
Set XBN Switch to Contact Mode

20 Point Multiplex Modules—Multiplex Binary
Unpowered Triac or SCR
If the XBN input is coming from a transmitter device with a triac or SCR
output, an AC source must power the output. If the transmitter does not
supply the AC power to the output, you must add the power externally.
Connect the AC voltage through a limiting resistor, as shown in Figure 15.
The following equation calculates the resistor to be used:
Resistor = Voltage - 1.6
Current
Supply
Holding
The holding current is listed in the triac or SCR rating.
Determine the wattage of the added resistor by either of these two
equations (power is doubled in the equations to accommodate safety
standards):
P = 2I2R or P = 2E2
R
where I is the load current, E is the source voltage (e.g., 120 VAC), and
R is the resistor.
Set the XBN switch to Voltage mode.
120 V
To create a voltage bias, add the power line and
resistor shown in the shaded area.
Add Resistor
Transmitter With
Triac Output
(e.g., power monitoring
transmitter or rate/flow
transmitter)
xbn13
Figure 15: Adding a Voltage Bias Circuit to an Unpowered Triac or
SCR Device