
Thank you for purchasing TOA's Flush-Mount Master Station.
Please carefully follow the instructions in this manual to ensure long, trouble-free use of your equipment.
N-8031MS
FLUSH-MOUNT HANDS-FREE
MASTER STATION
INSTALLATION MANUAL
1. GENERAL DESCRIPTION
The N-8031MS is a flush- or surface-mount master station
designed to operate in conjunction with TOA IP Intercom
Exchange and features high quality hands-free
conversation.
Connecting a foot switch or other external switch to the
external dial input terminal permits one-touch dialing
operation by way of such switches.
Handset conversation can be made in conjunction with the
optional RS-191.
2. WALL MOUNTING
2.1. In-Wall Mounting Using an electrical box
Attach the N-8031MS to the YC-241 Back Box or an
electrical box installed in a wall.
Note
The wall should be over 12 mm thick, and the opening in
the wall for an electrical box should be under 115 mm
(wide) by 254 mm (high).
The N-8031MS comes with 2 types of screws: oval head
combination screw M4 x 25 and oval head combination
screw UNC No.6 x 18.
For the electrical box provided with unified threads, use the
oval head combination screws UNC No.6 x 18.
Accessory screws
[Installation completion drawing]
Unit: mm
2.2. On-Wall Mounting Using a Wall-Mount box
Attach the N-8031MS to the YC-251 Wall-Mount Box
installed on a wall.
The N-8031MS comes with 2 types of screws: oval head
combination screw M4 x 25 and oval head combination
screw UNC No.6 x 18.
For the electrical box provided with unified threads, use the
oval head combination screws UNC No.6 x 18.
Accessory screws
Wall
surface
Acoustic material (accessory)
Note
Lay it down along the inside
of the box.
Wall
surface
Acoustic material (accessory)
Note
Lay it down along the inside
of the box.
YC-251
Wall-mount box
(option)
N-8031MS
Oval head combination
screw M4 x 25
(accessory)
N-8031MS
YC-241 Back box (option)
or 5-gang electrical box
Oval head combination screw
M4 x 25 (accessory)
254
18435
83.5
115

3. WIRING
3.1. Connection to the Exchange
To connect the cables from the N-8000EX/8010EX
Exchange to the N-8031MS, use the removable terminal
plug (2P) supplied with the N-8031MS.
The cables have no polarity.
3.2. Connection to RS-191
Connecting the RS-191 Option Handset to the N-8031MS
permits handset conversation.
Step 1. Remove the handset jumper attached to the N-
8031MS's handset connection terminal, then
insert it to the socket on the RS-191's rear PC
board.
Step 2. Install the ferrite clamp (supplied with the N-
8031MS) onto the RS-191's handset cables.
Then, connect the cables to the N-8031MS's
handset connection terminal.
Note
Though the socket on the PC board is faced inside, you
can insert the handset jumper into the socket from the
side.
Note
Run the cables along the ferrite
groove, and clamp them.
N-8000EX/8010EX Exchange
16 lines
Mini-clamp connector
(Supplied with the
E-7000TB
Terminal board
N-8000EX/8010EX)
Twisted pair cable
21
Removable terminal plug (2P)
12
(accessory)
Both upper and lower
terminals (clip terminals)
are internally connected.
RS-191 rear
N-8031MS rear
Socket
Handset connection terminal
Handset jumper
Ferrite clamp (accessory)
Line connection terminals
N-8031MS rear
Handset cable
Handset cable
RS-191
Handset connection terminal
N-8031MS

3.3. Connection to External Switch
External switches such as footswitches can be connected
to the N-8031MS's external dial input terminals.
Terning on each switch connected to the terminal [7], [8],
[9], or [C] permits the same operation as performed by
pressing the dial [7], [8], [9], or [C].
An electrical current of 1 mA flows through each contact.
Note
The cable length from the external switch should not
exceed 3 m.
3.4. The Type of Cables
The types of cables are to be determined according to the
following conditions.
• Twisted pair wires (such as those used for electronic
push-button telephone) are to be used for wiring
between the Exchange and the stations in principle.
• The number of cables pairs laid should be determined
considering the possibility of future expansion of the
system.
• Outdoor wires should be used where wiring passes
through inaccessible areas such as ceilings or under
floors where the maintenance is not performed. Indoor
wires may also be used, however, in case where there is
no risk of deterioration due to exposure to heat, etc.
Note
Specifications related to each junction are as follows.
Mini-clamp connector (N-8000EX/8010EX line terminal)
Conductor diameter: ø 0.4 – 0.65 mm (AWG22 – 26),
Solid wire
Outside diameter: ø 1.05 mm or below
Clip terminal (E-7000TB)
Conductor diameter: ø 0.4 – 0.8 mm (AWG20 – 26),
Solid wire
Outside diameter: ø 1.5 mm or below
Removable terminal plug (N-8031MS line terminal)
Conductor diameter: ø 0.4 – 1.6 mm (AWG14 – 26),
Solid wire/Stranded wire
External dial input terminal (N-8031MS)
Conductor diameter: ø 0.8 – 1.3 mm (AWG16 – 20),
Solid wire/Stranded wire
3.5. Relations Between Core Diameter of Cable
and Maximum Cable Length
Refer to the following chart as guidelines when designing
the distance between the Exchange and stations so that
loop resistance value becomes 170 Ω or less.
7
8
9
C
COM
External dial input terminals
7
8
9
C
COM
N-8031MS rear
8 mm
Cable
Press down.
External dial input
terminal block
Conductor Loop Maximum cable length
diameter resistance between the Exchange and station.
(mm) (Ω/ km)
ø0.4 295 570 m
ø0.5 187 900 m
ø0.65 113 1.5 km
ø0.9 58 2.9 km
(Assuming that the loop resistance is 170
Ω
.)

3.6. Terminal Station Connection
Mini-clamp connectors for line terminals and removable
terminal plugs for paging output terminal are supplied with
the N-8000EX/8010EX Exchange.
Perform each connector connection as follows.
Step 1. Cut off two-cable ends in equal length, and insert
them securely to a cover section (transparent
side) of the mini-clamp connector.
Note
Insert the cable without stripping the cable jacket.
Step 2. With a pair of pliers, lightly pinch the mini-clamp
cover and, after ensuring that the cable is
securely inserted, firmly squeeze on the cover.
Note
Squeeze on the mini-clamp cover until it is
correctly locked.
Step 3. Insert the wired connector (plug) into the
exchange's connector (socket) until it locks into
place.
3.7. Terminal Plug Connection
Step 1. Strip a cable jacket of approx. 5 mm from the
cable end.
Note
Do not solder plate on exposed inner cables
when using a stranded wire.
Step 2. Loosen the terminal screws and insert the cables.
Step 3. Tighten the terminal screws securely.
Notes
• Tug lightly on the cable to be sure that it does
not pull free. If the cable pulls free, loosen the
terminal screw again and reconnect from Step
2.
• To avoid stripping the screws, use the
screwdriver appropriate to the screws tightened
into the terminal plug.
Step 4. Insert the wired terminal plug into the pin header
on the N-8031MS's PC board.
133-06-268-9E
URL: http://www.toa.jp/
Cover
(transparent side)
Cable
5 mm
N-8000EX/8010EX Rear panel
Cable
Pin header
N-8031MS's
PC board
3
Tighten
Removable terminal plug
(accessory)
2
4
1 2