ALERTON MS/TP Microset II Operating instructions

Installation and Operations Guide
© Honeywell LTBT-MSTPMS2IOG Rev. 02
MS/TP Microset II

Important safety information and installation
precautions
Read all instructions
Failure to follow all instructions may result in equipment damage or a hazardous condition. Read all instructions
carefully before installing equipment.
Local codes and practices
Always install equipment in accordance with the National Electric Code and in a manner acceptable to the local
authority having jurisdiction.
Electrostatic sensitivity
This product and its components may be susceptible to electrostatic discharge (ESD). Use appropriate ESD
grounding techniques while handling the product. When possible, always handle the product by its non-electrical
components.
High voltage safety test
Experienced electricians, at first contact, always assume that hazardous voltages may exist in any wiring
system. A safety check using a known, reliable voltage measurement or detection device should be made
immediately before starting work and when work resumes.
Lightning and high-voltage danger
Most electrical injuries involving low-voltage wiring result from sudden, unexpected high voltages on normally
low-voltage wiring. Low-voltage wiring can carry hazardous high voltages under unsafe conditions. Never install
or connect wiring or equipment during electrical storms. Improperly protected wiring can carry a fatal lightning
surge for many miles. All outdoor wiring must be equipped with properly grounded and listed signal circuit
protectors, which must be installed in compliance with local, applicable codes. Never install wiring or equipment
while standing in water.
Wiring and equipment separations
All wiring and controllers must be installed to minimize the possibility of accidental contact with other potentially
hazardous and disruptive power and lighting wiring. Never place 24VAC or communications wiring near other
bare power wires, lightning rods, antennas, transformers, or steam or hot water pipes. Never place wire in any
conduit, box, channel, duct or other enclosure containing power or lighting circuits of any type. Always provide
adequate separation of communications wiring and other electrical wiring according to code. Keep wiring and
controllers at least six feet from large inductive loads (power distribution panels, lighting ballasts, motors, etc.).
Failure to follow these guidelines can introduce electrical interference and cause the system to operate
erratically.
Warning
This equipment has been tested and found to comply with the limits for a class B digital device, pursuant to part
15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference
when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate
radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause
harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause
harmful interference, in which case the user will be required to correct the interference at his own expense.
© 2012 Honeywell. All Rights Reserved.
6670 185th AVE NE
Redmond, WA 98052 USA
Phone: [phone] FAX: [phone]
Web Site: www.alerton.com
All information in this document is provided as is without warranty of any kind. Honeywell reserves the right to
change any information herein without prior notice. No guarantees are given as to the accuracy of information.
Trademarks and trade names may be used in this document to refer to either the entities claiming the marks and
names or their products. Alerton, BACtalk, and their logos are registered trademarks and VisualLogic is a
trademark of Honeywell. Honeywell disclaims any proprietary interest in trademarks and trade names other than
its own.
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2LTBT-MSTPMS2IOG Rev. 02 ©Honeywell

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Contents
© Honeywell LTBT-MSTPMS2IOG Rev. 02 3
Contents Quick reference 4
Quick reference (continued) 5
Introduction 6
Specifications 7
Mounting 8
Wiring 12
Wire specifications 12
Power supply guidelines and requirements 12
MS/TP Microset II power ratings 12
Power supply grounding and wiring 13
MS/TP LAN wiring 14
Terminating MS/TP LAN cabling 15
Grounding the MS/TP LAN shield 15
Terminating resistors 16
Operational overview 17
Hotel vs. office modes 17
Fan-control vs. no-fan-control modes 17
Cooling and heating setpoint calculation 17
After-hours override operation 18
Housekeeping override operation 18
English and metric units 18
Outside air temperature (OAT) display 19
LCD backlight operation 19
Testing the LCD backlight/ LCD/ and MS/TP status 19
Viewing communications status 20
Operating mode specifics 21
Enabling operating modes 22
Office modes 22
Hotel modes 30
Field service mode 35
Setting the MS/TP MAC address and BACnet device instance 38
BACnet object and property reference 39
MS/TP Microset II objects 40
Object properties 40
BV and AV assignments 43

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Quick reference
© Honeywell LTBT-MSTPMS2IOG Rev. 02 4
Quick reference
ID Display/control function Description Software remarks
1Setpoint (°F or °C as appropriate)
Override time remaining
ON/OFF status
Time of day (optional alternate)
Value associated with data code (field service
mode)
Displays unit setpoint, after-hours/housekeeping
timer, ON/OFF status, or value of field service
code, depending on mode of operation.
Optionally, in modes M1-M6, the time of day can
display alternately on a three-second cycle with
any of the above.
Setpoint = AV-90.
Housekeeping timer or after-hours timer =
AV-98.
ON/OFF mode = BV-65.
Time of day is read directly from the MS/TP
Microset II when BV-82 is ON. The MS/TP
Microset II must be time-synced. BV-83 controls
format (12- or 24-hour).
2Outside air temperature (OAT)
Outside humidity (optional alternate) Displays OAT. Optionally, an outside humidity
reading in %RH can display alternately on a
three-second cycle with the OAT.
OAT = AV-103, which is written to in MS/TP
Microset II.
%RH = AV-107. If AV-107 is non-zero display will
cycle.
3Fan status Displays occupant-selected fan status and speed
in modes M4, M5, M8, and M9. In these modes,
the occupant can use the right UP/DOWN buttons
to increase and decrease the fan speed. In other
modes, occupant adjustment is disallowed, but
DDC can control the fan status and speed
display.
Only one of the following BVs may be ON;
otherwise, the Microset II indicates a high fan
speed:
BLANK = BVs 72-74 OFF.
Low = BV-72 ON.
Med = BV-73 ON.
High = BV-74 ON.
4Space temperature
Space humidity (optional alternate for
MS-2000H)
Field service code (field service mode)
Displays space (room) temperature. With the
Microset II with humidity sensor
(MS-2100H-MSTP), the room %RH can display
alternately on a three-second cycle with the room
temperature.
Space temperature = AV-101. AI-0 is room
temperature as read by the Microset II
thermistor. Turn ON BV-75 to link AV-101 to
AI-0. Turn OFF BV-75 if using DDC to write
space temperature to ACV-101.
Display will cycle between space temperature
and humidity if BV-84 is ON.
Space humidity = AV-102. No DDC required.
AV-102 cannot store other values.
5Right UP/DOWN buttons
Fan speed control (M4, M5, M8)
After-hours increment/decrement (M2, M5)
ON/OFF control (M3, M6)
Housekeeping timer ON/OFF (M7, M9)
Adjust value (field service mode)
Button press causes only affected value on LCD
to appear; all others disappear. Display remains
in this state for three seconds after button
release.
Button press affects BV-67 according to mode
(see Table 5 on page 22). In fan modes, button
press also affects BVs 72–74 (Table 8 on page
43).
6Left UP/DOWN buttons
Adjust setpoint
Display unoccupied heating/cooling
setpoints (M2, M5)
Scroll through codes (field service mode)
Button press causes only affected value on
LCD to appear; all others disappear.
Display remains in this state for three
seconds after button release.

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Quick reference
© Honeywell LTBT-MSTPMS2IOG Rev. 02 5
Mode IDs
M1—Office, no fan, occupied
M2—Office, no fan, unoccupied
M3—Office, no fan, ON/OFF
M4—Office, fan, occupied
M5—Office, fan, unoccupied
M6—Hotel, no fan, rented
M7—Hotel, no fan, vacant
M8—Hotel, fan, rented
M9—Hotel, fan, vacant
See Table 5 on page 22 for more
information.
Field Service Codes
Code Data point Meaning
UC. AV-95 Unoccupied cooling setpoint
UH. AV-96 Unoccupied heating setpoint
CO. AV-93 Cooling offset
HO. AV-94 Heating offset
CS. AV-99 Occupied cooling setpoint
HS. AV-100 Occupied heating setpoint
AL. AV-97 Override limit
rO AV-108 Room temperature offset
hO AV-109 Space humidity offset
HI. AV-91 Setpoint high limit
LO. AV-92 Setpoint low limit
SP. AV-90 Occupant-selected space temperature setpoint
Quick reference (continued)

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MS/TP Microset II
6LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
Introduction The MS/TP Microset™II is a wall-mounted BACnet MS/TP smart sensor that
resides on an MS/TP network. It is designed for applications with multiple
zones, such as a restaurant or a shopping mall; or split zone control sites, like an
office setting where occupants share a single zone split into multiple working
areas.
Features:
• Supports MS/TP communications
• Outside and room humidity display
• Outside temperature displayed at all times
• Space (room) temperature displayed at all times
• Space (room) humidity displayed at all times
• Fan speed display/adjustment (up to three speeds and OFF)
• Setpoint display/adjustment
• After-hours/housekeeping overrides
• Optional time of day display
• Heating or cooling mode display
• English or metric units

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Specifications
© Honeywell LTBT-MSTPMS2IOG Rev. 02 7
Specifications
Table 1 MS/TP Microset II specifications.
Part Number MS-2100H-MSTP
Power 24 VAC @ 5 VA
MS/TP MS/TP LAN operates up to 115 Kbps
Dimensions 4.6" (117 mm) H X 3.0" (76 mm) L X 0.7" (18
mm) D.
Humidity Sensor
Accuracy
Operating Temp.
Repeatability
±5% RH, 10–90% RH @ 25°C.
-40–185°F (-40–85°C).
±0.5% RH.
Ratings EMC Directive 89/336/EEC (European CE Mark).
FCC Part 15, Subpart J, Class B.

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MS/TP Microset II
8LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
Mounting The MS/TP Microset II is designed to be wall-mounted indoors, with dimensions
ideal for mounting to a single-gang electrical box. See Fig. 3 on p. 10.
Mount in a clean, dry location away from windows, air ducts, and other places
where environmental factors may affect temperature and humidity readings.
Note If you mount the MS/TP Microset II on the interior of an outside wall,
thoroughly insulate so air behind the sensor doesn’t affect the sensor reading.
To meet requirements of the Americans with Disabilities Act, mount no higher
than 48" from the floor and with a minimum clear floor space of 30" X 48" (760
X 1220 mm). See Figure 1.
Figure 1 Mounting guidelines for compliance with Americans with Disabilities
Act (ADA).

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Mounting
© Honeywell LTBT-MSTPMS2IOG Rev. 02 9
Figure 2 Backplate mounting dimensions.
The MS/TP Microset II ships with the backplate on backwards. This makes the
backplate easier to remove during installation. Two screws attach the backplate
to an electrical box, mud ring, or other mounting surface.
To secure the MS/TP Microset II to a mounting surface
1. Remove the backplate from the MS/TP Microset II and the wiring
pigtail.
2. Flip the backplate so the smooth side faces the mounting surface.
3. Rethread the wires through the center knockout on the backplate.

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MS/TP Microset II
10 LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
4. Use communications grade connectors to splice the MS/TP Microset II
wires to the wire run of the MS/TP network. Alerton recommends using
communications grade connectors for splicing into the MS/TP network.
See “Wiring” on page 12 for details.
5. Secure the backplate to the mounting surface with the enclosed screws
or your own.
6. Hold the MS/TP Microset II at an angle above the backplate and then
slide it down.
7. The two tabs on the inside top edge of the MS/TP Microset II should fit
into the tab slots on the backplate
(see Figure 3).
8. Push the bottom of the MS/TP Microset II onto the backplate legs until
they snap securely on the tab-stops (see Figure 3).
CAUTION Do not crimp or kink the pigtail wires. See “MS/TP LAN wiring” on
page 14 for more wiring diagrams.
Figure 3 MS/TP Microset II mounting.
1.
Splice MS/TP Microset II
pigtails (Blue and Yellow) into
MS/TP LAN. Ensure that
connections are secure; use
comm grade splice connectors
instead of wire nuts.
2. Secure backplate to
mounting surface with
screws (provided).
3. Insert MS/TP Microset II tabs
into backplate slots.
5. Push bottom of MS/TP Microset
II until the backplate
legs click into position.
Backplate legs (face
away from wall)
MS/TP Microset II backplate
MS/TP Microset II pigtail
MS/TP Microset II
4. 24 VAC power =
White and Orange.

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Mounting
© Honeywell LTBT-MSTPMS2IOG Rev. 02 11
To remove the MS/TP Microset II from the backplate
1. Insert a thin, flat-tipped screwdriver into the last vent slot on the bottom
of the MS/TP Microset II. Position the screwdriver so that you can
apply pressure to the backplate leg (see Figure 4, bottom view).
2. Firmly depress the backplate leg until it is clear of the tab-stop on the
MS/TP Microset II.
3. Gently pull the freed corner of the MS/TP Microset II away from the
wall.
4. Repeat steps 1–4 on the other side.
5. Push upward on the bottom of the MS/TP Microset II until it is
completely free of the backplate.
Figure 4 Removal of MS/TP Microset II from backplate.
MS/TP Microset II backplate
Side view
Bottom view
MS/TP Microset II backplate
Backplate leg
Place screwdriver here to
depress backplate leg.
Repeat on other side.
Backplate leg
1. Insert screwdriver in
last vent slot and
contact backplate leg.
2. Push upward with
screwdriver, depressing leg
until it is free of tab.
3. Lift bottom corner
away from backplate.
4. Repeat on other side.
5. Push upward on
MS/TP Microset II until
free of
the backplate.

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MS/TP Microset II
12 LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
Wiring The MS/TP Microset II has a four-conductor connection to 24VAC power and
BACnet MS/TP.
Wire specifications Note Do not run MS/TP Microset II wire in the same conduit or alongside
building power cables. This can cause interference. If power cables must be
crossed, cross at 90°.
Power supply guidelines and requirements
The MS/TP Microset II uses 24VAC power from a UL Listed Class 2 - 24VAC
transformer (not provided). The MS/TP Microset II uses a half-wave rectifier to
convert the AC power supply to onboard power. This enables multiple MS/TP
Microset IIs to be powered from a single, grounded transformer.
CAUTION Half-wave devices and full-wave devices must not use the same AC
transformer. If a MS/TP Microset II will share its power supply with another
device, make sure that the other device utilizes a half-wave rectifier and that
polarity of wiring is maintained. Failure to do so can result in equipment
damage.
Figure 5 Internal MS/TP Microset II power wiring schematic, half-wave rectifier.
MS/TP Microset II power ratings
The MS/TP Microset II minimum current draw is 24 VAC @200ma leading to
5VA.
Table 2 MS/TP Microset II wire terminations.
Wire color Use
Orange 24 VAC Hot
White 24 VAC GND (neutral). Must be
connected to Earth ground, which acts as
the MS/TP reference plane.
Blue MS/TP +
Yellow MS/TP -

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Wiring
© Honeywell LTBT-MSTPMS2IOG Rev. 02 13
Power supply grounding and wiring
When connecting power to the MS/TP Microset II, ensure that one leg of the
VAC secondary circuit connects to a known earth ground.
Supplying a high-quality ground connection to a MS/TP Microset II is one of the
most important things you can do to ensure a trouble-free installation.
The 24VAC secondary leads are not interchangeable. Once a lead connects to
the GND wire on the MS/TP Microset II, it is the grounded lead. Observe and
maintain polarity for subsequent connections. The GND terminal provides a
reference ground for the circuit board and communications wiring. Use 18 AWG
cable for best results.
WARNING Ensure that all MS/TP Microset II power and communications
cabling are grounded according to these instructions. Failure to follow these
instructions may result in MS/TP Microset II operational and communication
failures or equipment damage.
Power supply wire selection
If you are considering long power supply wiring runs, using the right wire size is
critical. If the wire is too small, the resistance may be too high, resulting in a low
voltage supply. This is known as line loss. The wire size is based on the length of
the wire run and the current draw of the MS/TP Microset II. Use Figure 6 to
determine wire size; obtain additional information from the transformer
manufacturer.
Figure 6 MS/TP Microset II wiring recommendations

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MS/TP Microset II
14 LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
MS/TP LAN wiringThe MS/TP Microset II communicates on the site-wide BACnet system over a
twisted-pair MS/TP LAN, which uses the EIA–485 signaling standard. MS/TP
Microset IIs are master devices on the MS/TP LAN.
Each MS/TP Microset II employs a high-quality EIA–485 transceiver and exerts
¼unit load on the MS/TP LAN.
Table 3 MS/TP LAN facts
Transmission speed 9.6, 19.2, 38.4, 76.8, 115.2Kbps (configured at global
controller).
Layout Bus.
Cabling BACnet specifies the following. Shielded, twisted-pair cabling
with characteristic impedance between 100 and 130Ohms.
Distributed capacitance between conductors must be less than
30 pF/foot (100 pF/m). Distributed capacitance between
conductor and shield must be less than 60 pF/foot (200 pF/m).
Foil or braided shield acceptable.
Segment length 4000 ft. (1071 m.) per segment using recommended wire.
Maximum devices
overall Depends on classification of devices as master or slave. Maximum number of master devices is 128. Maximum number
of slave devices or devices overall (mixed master and slave) is
255. This includes VLCs, BACtalk global controllers (all are
considered masters) and any other devices, regardless of their
relative unit loads.
Maximum devices per
segment Depends on relative unit load of devices (see “Terminating MS/TP LAN cabling” on page 15).
Repeaters Required when making runs longer than 4000 ft. Three
repeaters maximum between any two devices.
Terminating resistors Matched resistors required at each end of segment bus wired
across (+) and (–). Use matched precision resistors rated ¼W
±1% / 80 - 130 Ohms.
Shield grounding Ground shield drain wire at single point earth (panel) ground,
not MS/TP Microset II ground. Tape off shield drain wire at
other end. Tie shield drain wire through at each MS/TP
Microset II.

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MS/TP LAN wiring
© Honeywell LTBT-MSTPMS2IOG Rev. 02 15
Terminating MS/TP LAN cabling
Maintain polarity of the MS/TP wire run throughout the MS/TP LAN.
Note Do not run MS/TP Microset II wire in the same conduit or alongside
power cables to avoid interference. If power cables must be crossed, cross at 90°.
IMPORTANT Always use communications grade connectors, such as 3M
Scotchlok or equivalent, when splicing pigtails with MS/TP LAN cabling.
Grounding the MS/TP LAN shield
Proper shield grounding of the MS/TP cabling can help minimize the risk of
communications problems and damage to equipment because of transient
voltage spikes (for example, lightning strikes).
Figure 7 Recommended MS/TP Microset II wiring: option 1
Figure 8 Recommended MS/TP Microset II wiring: option 2

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MS/TP Microset II
16 LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
Follow these guidelines for grounding MS/TP cable shields:
• Each MS/TP segment must have a single point of shield ground, as close
to the middle of the cabling run as possible (see Figure 9).
• Do not ground the MS/TP shield directly to a MS/TP Microset II wire.
• Never ground both ends of a shield because differences in potential
between the grounds may induce current on the shield, causing
interference.
• At connecting termination points, tie the shield through with a wire nut.
• At ungrounded, exposed shield points (the end of a segment), tape back
the shield to the wire jacket or, for optimum transient shunting, use
100V gas discharge tubes or 120V MOVs between the shield and
ground. See Figure 9.
Terminating resistors At the last device on each end of the MS/TP segment, matched terminating
resistors wired across MS/TP+ and MS/TP– are required for signal integrity.
Optimum segment performance typically requires “tuning,” a process by which
the value of the terminating resistors is selected based on the wave form of
signals on the segment. View wave forms using an industrial scope meter. The
goal is to have as square a wave form as possible with an amplitude greater than
200 mV. Resistors affect the wave form as follows:
• When the resistance value decreases, the amplitude of the wave form
decreases and becomes more square.
• When the resistance value increases, the amplitude of the wave form
increases and becomes less square.
Typically, precision resistors in the range 80-130 Ohms (+1%) yield acceptable
results. Ideally, the value of the terminating resistors should match the rated
characteristic impedance of the installed cable. For example, if the installed
MS/TP cable has a listed characteristic impedance of 100 Ohm, install 100 Ohm
matched precision resistors.
CAUTION Do not mismatch terminating resistors. Ensure that both resistors
on a segment have the same value.
Figure 9 MS/TP shield drain termination and tie through

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Operational overview
© Honeywell LTBT-MSTPMS2IOG Rev. 02 17
Operational overview
The MS/TP Microset II operates in one of nine modes. In each mode, the MS/TP
Microset II displays data and has operational features unique to that mode.
Operating modes are listed in Table 4 on page 21 and Table 5 on page 22.
Review the different MS/TP Microset II modes and determine which one is best
for your application. Then set BVs 64, 65, 80, and 81 according to Table 5 on
page 22.
BACtalk data displays can directly reference data points in the MS/TP Microset
II reserved for MS/TP operations. This offers the system operator flexibility and
ease of use—with a mouse click, the system operator can control MS/TP
Microset II operations.
Hotel vs. office modesBV-81 controls hotel and office mode (BV-81 ON = hotel). The primary
difference between hotel and office mode is the function of the after-hours timer
as compared to the function of the housekeeping timer. See “After-hours
override operation” and “Housekeeping override operation” herein. Other
operational details vary as well. See “Operating mode specifics” on page 21.
Fan-control vs. no-fan-control modes
BV-80 determines fan control mode (BV-80 ON = fan- control mode).
In fan-control modes, the occupant can select fan speed at the MS/TP Microset
II. Fan-control modes are typically used in fan-coil, air conditioning, or unit
ventilator applications.
In no-fan-control modes, the occupant is unable to select fan speed. However, if
desired, DDC can cause fan symbology to display at the Microset II.
No-fan-control modes are typically used in VAV or heat pump applications.
Cooling and heating setpoint calculation
The MS/TP Microset II calculates current heating and cooling setpoints (AV-99
and AV-100) using different logic in occupied and unoccupied modes (as read
from BV-67). Using the current setpoints (AV-99 and AV-100) in your control
DDC is most efficient because the MS/TP Microset II automatically calculates
these setpoints according to the operating status of the MS/TP Microset II.
Occupied setpoint logic (BV-67 ON)
• Current cooling setpoint (AV-99) = Occupant-selected space
temperature setpoint1(AV-90) + Cooling offset (AV-93) + Demand
offset (AV-106)
• Current heating setpoint (AV-100) = Occupant-selected space
temperature setpoint1(AV-90) – Heating offset (AV-94) – Demand
offset (AV-106)
1. The system’s setpoint high limit (AV-91) and setpoint low limit (AV-92) limit this value.

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MS/TP Microset II
18 LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
Unoccupied setpoint logic (BV-67 OFF)
• Current cooling setpoint (AV-99) = Unoccupied cooling setpoint
(AV-95)
• Current heating setpoint (AV-100) = Unoccupied heating setpoint
(AV-96)
After-hours override operation
Unoccupied office modes (M2 and M5) offer an after-hours override feature,
which enables the occupant to override a scheduled unoccupied status at the
MS/TP Microset II.
In override, the unit calculates current setpoints (AV-99 and AV-100) using
occupied setpoint logic (see “Cooling and heating setpoint calculation” on page
17). The occupant can increase or decrease the timer to the next half-hour
increment. The occupant can also adjust the setpoint and fan speed (if
applicable).
The after-hours timer (available in software as AV-98) automatically counts
down whenever it is set to a non-zero value.
To disable this feature, set the after-hours timer limit (AV-97) to zero.
DDC can read override status from BV-66, which is ON if the after-hours timer
is non-zero. When BV-64 (occupied/unoccupied command) is ON, the
after-hours timer automatically resets to zero.
Housekeeping override operation
Vacant hotel modes (M7 and M9) offer a housekeeping override. This is similar
to the after-hours override in that it causes occupied setpoint logic to be in effect.
However, there are important differences: the occupant can only start and stop
the timer (timer adjustment is not allowed); the override timer limit (AV-97) is
read in minutes, not hours; and the occupant can’t adjust setpoint or fan speed.
This feature can be disabled by setting the override timer limit (AV-97) to zero.
DDC can read override status from BV-66, which is ON if the housekeeping
timer is non-zero. When BV-64 (occupied/unoccupied command) is ON, the
housekeeping timer automatically resets to zero.
English and metric units
You can set the MS/TP Microset II to display English or metric units based on
the selection in the DDC header file or you can toggle that status in software.
The English or metric setting is referred to as the native units mode.
BV-69 can be set ON to reverse native units mode for the
MS/TP Microset II display. Thus, if the MS/TP Microset II is set to English, and
BV-69 is ON, the MS/TP Microset II displays units in appropriate metric
equivalents. This enables the system to display units at the MS/TP Microset II
according to occupant preference without a programmer having to write separate
DDC sequences around each unit of measure.

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Operational overview
© Honeywell LTBT-MSTPMS2IOG Rev. 02 19
Outside air temperature (OAT) display
For OAT read at another unit to display at the
MS/TP Microset II, the OAT value must be written in BCM DDC to the Present
Value of AV-103 in the MS/TP Microset II.
LCD backlight operation
The MS/TP Microset II requires 24VAC (white and orange wires) to operate.
BV-79 controls backlight operation. If BV-79 is OFF, the backlight turns ON
when any button is pressed and stays on for 20 seconds after there is no button
activity. If BV-79 is ON, the backlight is ON continuously.
Testing the LCD backlight/ LCD/ and MS/TP status
You can test the LCD to ensure that it is functional.
To test the LCD backlight
1. Turn ON the LCD backlight by turning ON BV-79.
Verify the backlight is ON.
2. Turn OFF the LCD backlight by turning OFF BV-79.
Verify the backlight is OFF.
3. Turn ON the LCD backlight again by turning ON BV-79.
Verify the backlight is ON.
To test the LCD and MS/TP status
1. Press and hold the left UP and right DOWN buttons simultaneously.
All LCD items should be visible.
Note After 5 seconds the test ends and MS/TP communication status is
displayed. The LCD returns to normal operations when the buttons are released.

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MS/TP Microset II
20 LTBT-MSTPMS2IOG Rev. 02 ©Honeywell
Viewing communications status
• If the MS/TP Microset II sees no MS/TP packets, “no” displays.
• The MS/TP MAC address is displayed in the outside area.
• If it sees valid MS/TP requests, then “r” displays.
• If it sees valid MS/TP headers, then “h” displays.
• If it sees valid MS/TP headers or requests, then the baud rate displays in
in digits. For example, 9.6, 19.2, 38.4, 76.8, or 115.