Alpha NH201TT-3 User Manual

APPLICATION

NH201TT-3 Amplifier and Power

Supply Installation and Use Instructions

Used with the HT2001 Series

Inside Handset Intercom Stations

The NH201TT-3 series intercom system allows one or
more HT2001 series inside handset stations to communi­cate with one or more door entry stations, and to release the
door opener at each door entry station. A number of
optional accessories are available to provide a complete
entry intercom signaling and communications system.

PROCEDURE

1. Read installation instructions for each unit to determine
equipment location and installation method.

2. Install housings and wiring.

3. Install equipment.

4. Check wiring and connect. Observe all local and
national electrical and building codes.

5. Apply power and check operation.

HOUSING INSTALLATION AND

EQUIPMENT LOCATION

INSIDE HANDSET STATIONS

Locate stations where needed at convenient speaking height,
about 4.5 feet (137cm) from the finished floor. Handset
can be secured directly to the finished wall surface or can
be mounted over a single gang electrical 'gem' box or single
gang electrical plaster ring.

OUTSIDE STATION(S)

Locate door station(s) at convenient speaking height on
exterior wall near entrance. Make sure you comply with all
national and local electrical and building codes.

NH201TT-3 AMPLIFIER/POWER SUPPLY

The NH201TT-3 is usually located inside of each lobby/
entry panel door station. It can be 'snapped' into a 'TT'
series door station behind the plastic speaker grille, or
mounted inside of other types of compatible door entry
stations. It must be located away from any source of direct
heat or extreme cold and in an accessible location. Keep at
least 3 feet (1 meter) away from transformers, AC power

wiring, transformers, fluorescent lights, light dimmers and
other electrical devices. Protect cable from damage. Shielded
cable should be used if interference is a concern.

DOOR RELEASE

Run 2 conductor #18AWG from the electric door release
location to the NH201TT-3 amplifier. If distance is greater
than 50 feet, use #16AWG cable. Use a separate cable from
the intercom cable, and route away from any intercom
wiring.

CONNECTIONS

Before connecting, make certain wires are free from shorts
or grounds. Make connections as shown on page 4 and as
detailed in the following instructions.

INSIDE HANDSET STATIONS

1. Connect terminals 'I' and 'II' on handset stations to
terminals 'I' and 'II' on other handset stations and to
terminals 'I' and 'II' on the amplifier.

2. Connect terminal 'S' on each individual handset station
to the corresponding push-button at the entry door
station, that is used to signal that handset station.

3. Terminals 'Z' and 'K' on each handset station are
optional terminals, and are only used if the 'Red Dot'
push-button needs to be used to operate an optional
function.

DOOR ENTRY STATION

1. Connect speaker/microphone terminals 'L1' and 'L2'
on door entry station to terminals 'L1' and 'L2' on the
NH201TT-3 amplifier (done at the factory).

2. Connect speaker/microphone terminals 'M1' and 'M2'
on door entry station to terminals 'M1' and 'M2' on the
NH201TT-3 amplifier (done at the factory).

NOTE: The NH201TT-3 amplifier comes factory­wired with the L1,L2,M1 and M2 speaker/microphone
connections already installed onto the amplifier.

TRANSFORMER

1. Connect transformer 12VAC terminals to the (2)
12VAC input terminals ('12v') on the NH201TT-3
amplifier/power supply. Do not use this transformer to
power any other device, not included on this system.

2. Do not plug T1240 transformer into electrical outlet or
connect transformer primary to 117 VAC until entire
installation is complete and checked.

Copyright© 2013, Alpha Communications®, All Rights Reserved.

AWD175 Rev. 1 (03/2013)

DOOR OPENER

1. Connect one wire coming from door opener to the specific
amplifier terminal '12v' (near terminal 'R' - see diagram).

2. Connect one wire coming from the 12VAC door opener to
amplifier terminal TOE'.

NOTE: Use proper gauge wiring to door opener.

NOTE: POLARITY OF AC TYPE DOOR OPENER
TERMINALS IS NOT CRITICAL.

FINISH INSTALLATION

1. Install stations on housings. Do not overtighten screws.

2. Install amplifier and accessory devices as needed.

3. Plug T1240 transformer into outlet. If hard-wired trans­former is used, connect primary to 117 VAC. Observe all
local and national electrical codes.

TEST AND CHECKOUT

1. At all inside handset stations, make sure the handsets are
hung-up and seated properly on the cradle switch, and
that no wires were 'pinched' when handset covers were
affixed.

2. Check each unit in the system for operation in accor­dance with the operating instructions.

3. If feedback occurs between stations, reduce volume.
Amplifier volume control is preset at the factory, but may
be readjusted, if necessary.

TROUBLESHOOTING

If the system fails to operate as required, review operating
instructions again. If the equipment fails to operate as
indicated in the instructions, check the following points:

1. ENTIRE SYSTEM DEAD: Check 12VAC at transformer

secondary; wiring between transformer and NH201TT-3
amplifier; connections at amplifier terminals and for 117
VAC at transformer primary.

2. NO CALL UP BUZZER AT HANDSET: Check for

approx. 12VAC at terminals 'II' and 'S' on handset, when
entry station pushbutton is depressed. Temporarily switch
handset with one from a functioning location. Check
wiring connections at remote handset. Check that wiring
inside handset base is not restricting movement of buzzer
clapper; temporarily switch handset to another location
that is functioning, and try again. Check that entry station
pushbutton is making contact, by shorting out the two (2)
wires on the back of the button.

3. NO VOICE ON SYSTEM: Check volume control (poten-

tiometer) on NH201TT-3 amplifier (in both directions; up
and down). Check terminals 'I' and 'II' to handsets. Check
speaker/microphone connections at each entry door sta­tion. Disconnect terminals 'I' and 'II' on NH201TT-3
system amplifier, and connect a single handset to those
terminals. If voice is working, amplifier and entry speaker/
microphone are O.K., so check riser wiring. If not,
amplifier or speaker/microphone could be faulty. Check
by replacement.

NOTE: The Alpha Communications® warranty is void if this
system is installed or used in any manner other than described
in this manual.

OPERATING INSTRUCTIONS

OUTSIDE DOOR STATION
TO CALL HANDSET: Push button on outside door station
to signal inside handset. An electric buzzer will be heard at the
inside handset station. If the electric buzzer has been replaced
by the optional model R2007 AlphaTone™ unit, an electronic
chime sound will be heard at the handset station.

INSIDE HANDSET STATIONS
TO REPLY: Lift the inside handset off of its cradle and
speak in a normal voice. Conversation is full duplex type
(simultaneous talk and listen). If satisfied with the identity of
the caller, you may depress the 'Key Symbol' push-button to
electrically open the entrance door (if so equipped). An AC
type door opener will 'buzz' while operating, indicating permis­sion to enter. When conversation is completed, hang-up
handset on its cradle.

4. UNABLE TO RELEASE DOOR STRIKE: Check wiring

to handset terminals 'I' and 'II'. Temporarily remove door
opener wire going to amplifier terminal 'TOE' and touch to
the terminal '12v' on amplifier nearest terminal 'R'. Check
operating voltage of door opener matches output from
system amplifier. Check wiring (and gauge) to door
opener, from amplifier/power supply. When using a
magnetic type lock or other 'fail-safe' type door lock, you
should use a reversing relay, such as our model# PK407A
for each entrance.

5. HUM OR BUZZ: Check system wiring installed too close

to power wiring or electrical devices or transformers;
check transformer(s) installed too close to control equip­ment (should be at least three (3) feet away). Wiring is
being run next to wiring for other systems and/or devices.

6. SQUEALING OR HOWLING: Check amplifier volume

control set too high; check for loose speaker/microphone
at door entry station(s).

7. UNABLE TO TALK TO DOOR STATION: Check

terminals 'I' and 'II' going from handsets to amplifier for
continuity and shorts, grounds, etc. Check for proper

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functioning of door entry station speaker. Check for
approx. 50 ohms between terminal 'L1' and 'L2' on
speaker microphone (with system wiring disconnected).

8. UNABLE TO LISTEN TO DOOR STATION: Check

terminals 'I' and 'II' going from handsets to amplifier for
continuity and shorts, grounds, etc. Check for proper
functioning of door entry station microphone.

If these checkpoints fail to indicate the problem, there may be
an equipment fault. Contact the factory or qualified service
representative.

INSTALLING THE R2007 AlphaTone™: When you
wish to replace the standard AC buzzer in the HT2001 or
HT3001 series handsets with the optional model R2007
AlphaTone™ unit, please follow these instructions below:

1. Locate the silver AC buzzer attached to the handset base.
Remove the set screw (and keep it for re-use).

2. Gently pull up the two (2) wires from the buzzer that are
attached to the internal p.c. board. Carefully slide the wires
off of the connecting posts.

3. Install the R2007 AlphaTone™ in place of the buzzer,
using the buzzer set-screw.

4. Install the two (2) wires onto the p.c. board, using the
same connecting posts that the buzzer used. Polarity does
not matter.

5. Position the wires inside the handset base, so they will not
get 'pinched' when the cover is placed over the base.

6. Using a small screwdriver, you can change the AlphaTone's
sound, by adjusting the built-in potentiometer found on the
p.c. board of the R2007.

HT2001 Series

HT3001 Series

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TYPICAL WIRING LAYOUT DIAGRAM

FOR A SINGLE ENTRANCE SYSTEM

Notes:

1. Use #18AWG wiring to transformer and door opener (up to 50 feet max.). All other wiring can be #22AWG.

2. Talk down volume can be adjusted using volume control (potentiometer) on NH201TT-3 amplifier/power supply.

3. When connecting to a magnetic door lock or other 'fail safe' type door lock, use the optional model PK407A
specialty relay, for each entrance door lock.

4. If the NH201TT-3 amplifier is not mounted behind the entry door station, and is mounted remotely, we
recommend using shielded cable from the speaker/microphone wires to the NH201TT-3 amplifier/power supply.

5. Transformer wiring MUST NOT be in same cable as handset wiring!!!

6. Observe all local and national electrical and building codes.

7. All terminals connections shown may not be in the order that they appear on the equipment.

ALPHA COMMUNICATIONS® • 42 Central Drive • Farmingdale NY 11735-1202

TOLL-FREE TECHNICAL LINE 1-800-666-4800 • Phone: [phone] • Fax: [phone]

WEBSITE: www.AlphaCommunications.com • EMAIL: [e-mail]

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