Dwyer RSM User Manual

Bulletin P-3-RSM

Series RSM Room Status Monitor

Specifications - Installation and Operating Instructions

The Series RSM Room Status Monitor is designed for critical low

differential pressure applications that require stringent pressure
monitoring and alarming. The Series RSM can be configured to monitor
positive or negative pressure in protected environments and hospital
isolation rooms per CDC guidelines. The RSM is a complete system that
includes a backlit RGB LCD display with a graphic user interface which
enables access to pressure, security, calibration, and alarm setup. The
touch-screen displays menus that guide the user through setup, as well
as setting up password protection. Red and green LED's and a local
audible alarm (with time delay feature) alert personnel to system status.
The RSM has a NEMA 1 (IP20) rated fire retardant plastic for indoor
applications. True differential pressure is displayed with a resolution of

0.001 in w.c. The very low pressure capacitance is dead ended and
avoids the potential for cross contamination of the room and reference
space as well as eliminating drift that results from fouling of flow based
sensors, which by nature have a flow path connecting the protected and
reference spaces. Additionally, there are two levels of password
protection available as well as optional BACnet MSTP communication.

1.0 INTRODUCTION

Congratulations, and thank you for purchasing Dwyer Instruments’
Room Status Monitor (Series RSM). Its ease of operation and durable
construction will provide years of reliable service. While the Series RSM
is easy to operate, it is advisable to read this guide carefully before use.
It is designed to help you take full advantage of the function and
performance of the Series RSM.

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ROOM STATUS MONITOR

SPECIFICATIONS
Service: Air or nonconductive, nonexplosive gases.
Accuracy: ±0.5% FS, ±0.25% FS (optional).
Temperature Limits: 32 to 120°F (0 to 50°C).
Humidity Limits: 5 to 95% Relative humidity (non-condensing).
Altitude: 6561 ft (2000 meters) max.
Thermal Effects: ±0.03% FS / °F (± 0.05% FS / °C).
Pressure Limits: 15 in w.c. (±3.7 kPa).
Supply Voltage:

Order Code A (24 VAC): 18 to 32 VAC, 50 to 60 Hz.
Order Code B (120 VAC): 85 to 265 VAC, 50 to 60 Hz.
Main supply voltage fluctuations up to 10%.

Power Consumption (Voltage output): 5 W.
Output Signal: Selectable 4 to 20 mA (2-wire), 0 to 5 VDC (3-wire), or

0 to 10 VDC (3-wire).

Loop Resistance (4 to 20 mA output): 0 to 510 Ω.
Electrical Connection: Removable terminal block.
Process Connection: Barbed fittings for 3/16˝ I.D. tubing.
Enclosure Rating: NEMA 1 (IP20) rated for indoor app lications.
Housing: Fire retardant plastic.
Mounting: Mount to standard double gang metal electrical box using 4x4˝

plaster ring adapter.

Dimensions: 8˝ H x 5.4˝ W x 1.8˝ D (20.3 H x 13.7 W x 4.1 D cm).
Weight: 1.5 lbs (680 g).
Communications: BACnet MSTP ASC optional.
Agency Approvals: CE, CSA (RSM only).

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TUBING HEADER PORT

SPEAKER

ALARM

ACKNOWLEDGE

BUTTON

A-285 REMOTE
ANNUNCIATOR

LED
INDICATORS

1.1 INTENDED USE

The Series RSM is designed to monitor critical air environments,
providing room static pressure indication, alarming, and communication
functions. The applications include:

1. Hospitals - patient isolation and protection rooms, operating suites,
intensive care and emergency rooms.

2. Pharmaceutical, semiconductor, precision, manufacturing and clean
rooms.

3. Laboratories - medical research and BSLs (Bio-Safety Labs),
radiation, toxic metals and chemicals.

DWYER INSTRUMENTS, INC.

Phone: [phone] www.dwyer-inst.com

P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: [phone] e-mail: [e-mail]

1.2 RSM FUNCTION

The Series RSM senses very low differential pressure using high accuracy
capacitive sensor technology. The pressure difference for these
applications is the difference in static pressure between a critical
environment room and its surrounding reference area (usually a hallway or
another room). Maintaining and monitoring a static room pressure
difference ensures that the critical environment room is either protected or
isolated from a surrounding environment. Protection strategy requires a net
positive room static pressure difference, while isolation requires a net
negative static pressure difference. The RSM can be programmed to
monitor either positive or negative room static pressure. The RSM low
pressure sensing technology is coupled with multifunctional alarming and
simple touch-screen user interface with password security protection. The
BACnet communication option allows the device to communicate with
other BACnet devices to allow the supervisory system to change
configuration setups and monitor alarms in an open network.

3.3 MOUNTING

CAUTION

(For 120/240 VAC Version Only): Do not open or remove RSM cover

(flathead screwdriver required) with input power applied unless performed
by a licensed electrician. “Hazardous Live” voltage is present at connector
J3 when power is applied. Please observe the warning symbol ( ) near
the J3 power connector.

The RSM is designed to be mounted on a standard double gang metal
electrical box using a 4˝ x 4˝ plaster ring adaptor. Remove the RSM cover
and mount the baseplate to the plaster ring adaptor using four 6-32, 1/2˝
long mounting screws. Note: The plaster ring external mounting face needs
to be positioned flush to recessed, relative to the surface of the wall. Also
note the orientation of the 4 mounting screws in the plaster ring, as the
plaster ring is rotated 90° from conventional mounting.

User Interface: LCD display 128 x 128 COG module, with custom RGB
LED backlight and custom 4-wire resistive touch screen.

RGB Backlight: The SRPM indicates the status of the room being
monitored using visual backlight color.

Color status:
Green — Room pressure is within alarm limits.
Yellow — Door is open (door input must be enabled).
Red — Room pressure is outside alarm limits and alarm delay period has
been exceeded.

Visual Feedback: LEDs, green for normal, red for alarm.

Audible Feedback: Buzzer will sound when pressure is out of range and

alarm delay has timed out. Volume can be adjusted between 1 to 4 in
relative sound levels up to the max level spec of the buzzer of 85 dB at 4˝.
Audible alarm can also be disabled.

Quick Room Mode Change: Sometimes the room needs to be changed
quickly from in use (Occupied) to out of use (No Isolation). This is
accomplished by using two levels of password protection. The Operator
level allows access to change room modes but no other changes. The
Supervisor Level allows full access to all menus. In No Isolation mode no
alarms are generated even if the pressure is outside limits. To change
modes press the Menu key, press Setup Room key and press No Isolation.

2.0 PARTS LIST

2.1 RSM INCLUDED PARTS

Quantity
1 RSM assembly
2 Barbed Coupling, Brass
2 1/4˝ Tube, Silicone, Inter-Connect
4 6-32 x 1/2” Mounting Screws for RSM Base

3.4 WIRING ELECTRICAL BOX (ROUGH IN)

Layout the system in terms of wiring: power, annunciator, analog output,
BACnet, relay output and plumbing to connect to the monitored spaces
(pressure taps). Bring all power, earth ground, signal communications and
analog output wiring into the 4˝ x 4˝ electrical box. In order to conform to
the CSA safety standard the electrical installer must comply with the
following ground earth instructions. Pre-wire electrical box with power (24
VAC or 120/240 VAC depending on RSM model), and provide grounding to
the electrical box and plaster ring adaptor. The safety ground path consists
of the four 6-32 x 1/2˝ metal screws that connect the RSM metal base to
the 4˝ x 4˝ metal plaster ring. The plaster ring is grounded to the 4˝ x 4˝
electrical box by 2 mounting screws. The 4˝ x 4˝ electrical box is grounded
to the building earth ground. It is also highly recommended to use armored
cable (Type AC) for all the wiring in applications where high levels of radio
interference may be present.

Power leads and wiring should be 14 to 22 AWG braided wire. 18 AWG
braided wire is recommended for wiring J3 power connector to RSM. For
120/240 VAC the hot wire connects to L and neutral to N (See Section

13.0). BACnet suggested wiring is 22 AWG stranded wire in a shielded
cable, a +, -, Gnd (S) and shield should be run. This can be two twisted
pairs with a separate cable shield. One twisted pair is used for
communications, the second twisted pair can be used for communications
ground and the shield wire can be connected to the other device shield
wires.

2.2 OPTIONAL A-285 INCLUDED PARTS

Quantity
1 Annunciator Assembly

3.0 MOUNTING AND WIRING

To mount and install properly, the following components are required:

3.1 NOT INCLUDED RSM PARTS

Quantity
1 Double Gang Metal Electrical Box with Grounding Stud
1 4˝ x 4˝ Metal Plaster Ring
1 Door Switch SPDT or SPST, N.O., as needed

3.2 NOT INCLUDED A-285 PARTS

Quantity
1 Single Gang Electrical Box

Note: In the following wiring sections, abbreviations are used (e.g. J1, P3).
Please see section 13.0 for complete wiring diagrams with abbreviations.

Mounting Screws [x 4]

3.5 ATTACHING PRESSURE TUBING

Typically a Room Pressure Snubber (RPS) is installed in the monitored
room.

NOTICE

overpressure from crimped or collapsed tubes.

Use the following procedure for all room types positive, negative or neutral:
Typically a Room Pressure Snubber (RPS) is installed in the monitored
room. Often stiff nylon 3/4˝ tubing is used for running pressure signals from
the SRPM to the monitored spaces. To prevent buckling and collapse of
this stiff tubing inside the electrical box, use the supplied soft silicone
tubing and tubing adapters to transition from the field tubing to the pressure
fittings on the RSM. Attach pressure tubing as follows:

1. Connect the 1/4˝ O. D. tubing from the RPS to the 4˝ x 4˝ electrical box

for the RSM by pushing the 1/4˝ tube onto one end of the barbed, male to
male, tube adaptor, then push the silicone tube (supplied) onto the other
end. Thread the tubes, with installed adaptor, through the conduit opening
at the bottom of the electrical box.

Always attach tubing to the RSM header and then
place Header onto RSM. This will prevent

4.2 AUDIBLE ALARM

Alarm potentiometer can adjust from 0 to 85 dB. Using a screwdriver, rotate
potentiometer (on A-285 remote annunciator PC board) clockwise to
increase volume and counterclockwise to decrease volume.

Audible Alarm
Potentiometer

2. Next push the open end of the silicone tubing onto the RSM pressure

tube header (H1) port labeled “+”. Note: The header is an Electro­Pneumatic (EP) assembly. “+” indicates (Positive) pressure, and “-”
indicates negative or reference pressure.

3. For the most pressure stable operation, an RPS installed in the

reference pressure area is also recommended. In this case, install the RPS
in a hallway or anteroom. Attach the tube to the RSM in the same way as
in step 2, except attach the tube to the “-” port on the pressure tube header.
Tighten swivel fittings on the assembly if they become loose.

4.0 ALARM RELAY OUTPUT

The Single Pole Double Throw (SPDT) relay output can be used for remote
signaling of alarm condition. A form “C” contact rated at 1A is available.
Connect to J4, P1 and P4 (See Section 13.0).

4.1 OPTIONAL REMOTE ANNUNCIATOR WIRING

Dwyer offers an optional Remote Annunciator (Model A-285). In the figure

below, the remote annunciator connector is at left, and the RSM connector
is at right: Connect P1 to P2, then connect P2 to A1 (Located on Remote
Annunciator), finally connect P3 to A2 and P4 to A3.

5.0 DOOR STATUS SWITCH WIRING

5.1 WIRING

Install the door switch into the door jamb. Wire to the normally open (N.O.)
side of the door jamb contact switch. The SRPM will indicate the status of
door position. A contact closure indicates that the door is closed. This is a
low voltage circuit (5 VDC). Run two wires from the door switch to
connector J6 on the SRPM. The door input status function is enabled in the
ALARM SETUP SCREEN, section 7.5.

6.0 ELECTRICAL INSTALLATION

6.1 ANALOG OUTPUT

The RSM can be configured to have current (4 to 20 mA) or voltage (0 to
5 or 0 to 10 VDC) outputs. Voltage output--pin 1, Current output--pin 2,
Common--pin 3. Note: No external excitation is required.

Current Output

Voltage Output

6.2 BACnet Communication

BACnet hardware is implemented as isolated RS485. Wire to Connector
J2, labeled RS-485. Connect tx line to +(A), rx to -(B) and ground wires to
S. Connect Shields together with wire nut. Hardware configuration is done
using a 5 position dip switch located in the upper right hand section of the
PCBA as well as through the touch screen interface.

Position Function

1

MAC address enable

2

N/C Not Connected

3

Pull Up Resistor

4

Termination Resistor

5

Pull Down Resistor

Use a small flat blade screwdriver or pen to push the switch to the right to
turn that function on, otherwise it is off. There is a BACnet setup screen
that is enabled by pushing position 1 switch to the on position. After
configuration the switch must be moved to the off position.