BT Redcare GSM STU EV Troubleshooting guide

User/Installation Guide
GSM STU EV

CE MARKING
The GSM* STU* carries the CE approval marking in accordance with the CE
Marking Directive 93/68/EEC. The GSM STU EV complies with the following
European Directives:-
73/23/EEC (Low Voltage Directives)
by compliance with safety specifications:-
EN60950 User Safety
EN41003 Network Safety
89/336/EEC (Electro Magnetic Compatibility Directive) as amended by 92/31/EEC
by compliance with EMC specifications:-
EN55022 Emissions Class B
EN50130-4 Immunity
99/5/EEC (Radio and Telecommunications Terminal Equipment Directive)
2002/96/EC (Waste Electrical and Electronic Equipment Directive)
Suitable for use in systems that comply with EN 50131-1 at:
Security Grade 4, Environmental Class 1.
* GSM = Global System for Mobile communications
* STU = Subscriber Terminal Unit

Table of Contents
INTRODUCTION 3
Static Sensitive Devices 3
Decommissioning Procedure 3
GSM STU EV OVERVIEW 5
Specifications 6
GSM STU Compatibility 7
3GSTU Replacement 7
Redcare GSM Connection 7
Safety Statement 7
Siting 8
Power Supply 8
Line Compatibility 9
REN 9
INSTALLATION 11
Training Courses 11
Pre-installation Requirements 11
CPE Number 11
Connecting The Telephone Line And Earth 12
Antenna 13
Mains Fail 15
Tamper 15
Power Connection 15
Alarm Inputs 15
Plug-in Compatibility Link (Lk3) 17
Output Relays 17
Control Output 18
Return Path Signalling Output (RPS) 18
Line Fault Relay 18
ATS Test 19
Telephone Line Selection (Lk1) 19
NVM 21
Remote Programming 22
Pin Alarm Polarity 23
Learning Procedure 23
Programming The NVM 26
STATUS INDICATORS 32
STU Status LED Meanings 33
SYSTEM COMMISSIONING 36
Testing The System 36
Warranty 37
Repairs 37
TROUBLESHOOTING 38
Chirps 38
Substitution 38
Equipment Compatibility Issues 38
DISPOSAL 43

Introduction
Static Sensitive Devices
Static electricity is present in our everyday lives. A static charge is generated by friction and the separation of two
dissimilar materials. An imbalance of electrons causes a potential difference of many hundreds of volts. On discharge, a
large current flows for a short time.
Many electronic components can be damaged by such static charges. Component failure may not be immediate or
catastrophic. Electro-Static Discharge (ESD) can cause hidden damage to components, which will affect their reliability.
It is recommended that precautions are taken against damage due to static electricity during the installation and
maintenance of the GSM STU EV. Suitable ESD protection measures include ensuring that you are earthed (via a wrist
strap and a 1 MΩ resistor) whenever you handle the unit.
Decommissioning Procedure
Important:
If the GSM STU EV is in service, the Alarm Receiving Centre (ARC) must be contacted to decommission it before it is
power cycled. You must follow these decommissioning instructions when there is a need to change the alarm system
settings:
1. Call the ARC and request they decommission the GSM STU EV.
2. Wait for the ARC to confirm that the GSM STU EV is decommissioned.
3. Turn off the power to the alarm system completely (i.e. switch off the mains and disconnect the battery).
4. Make the desired changes to the alarm system.
5. Re-connect the battery and switch on the mains to re-apply power to the GSM STU EV.
6. Request the ARC re-commission the GSM STU EV.
7. Test the system (see page 36).
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GSM STU EV Overview

GSM STU EV Overview
The GSM STU EV is a combined Public Switched Telephone Network (PSTN) Subscriber Terminal Unit and wireless alarm
reporting device for the redcare gsm service.
The GSM STU EV system is designed to provide a backup communications path for the single landline connection to a
premises. This allows alarms to continue to be transmitted even in the event of a landline communications failure.
The Alarm Receiving Centre (ARC) will be able to continue to monitor a premises following a landline cut. It also allows line
faults (as distinct from malicious line cuts) to be more positively identified. A malicious line cut will usually be accompanied
by an intruder alarm transmitted over the GSM path.
In addition, the GSM signal strength is constantly monitored. Should this fall below a certain level, an alarm message will
be transmitted via the landline indicating that there is a GSM fault.
During normal operation, the GSM path does not pass any data and all signalling is via the BT landline.
The GSM link becomes active:
• During the GSM STU EV commissioning sequence.
• If the GSM STU EV detects a landline communications failure.
• When the landline has failed and a pin alarm occurs.
• When a routine GSM connection test is being performed.
• If a message transmitted across the landline is not acknowledged
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Specifications
Power supply requirements:
Voltage: 10 V DC to 15 V DC
Current: 350 mA peak @12 V DC (Required rating of power supply)
160 mA mean @12 V DC (For standby battery capacity)
Ripple/noise: 200 mV p-p max.
Low battery threshold (detected by GSM STU EV): 10.8 V ± 0.2 V
Pin alarm inputs:
Logic High = +3.5 V to +30 V
Logic Low = -0.5 V to +0.8 V
Logic level outputs: (on sockets SK1 and SK2)
Logic High = 3.8 V @ 560 μA max
Logic Low = 0.4 V @ 280 μA max
These voltages are with respect to the 0V terminal on TB1
Relay contacts:
30 V, 1 A Max
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GSM STU EV

Physical:
Size = 168 x 115 x 36 mm
Mass = 360 g
Environmental:
Operating ambient temperature +5° C to +40° C
GSM STU compatibility
For instances where the GSM STU EV is required to behave in an identical fashion to a GSM STU, the NVM should be
removed and the link LK3 be fitted to position P16. This mode of operation disables the ATS test functionality and
permits pin inputs 10 and 11 to be used if required.
3GSTU Replacement
The GSM STU EV has been designed as a replacement for existing 3GSTU installations where there is a need to upgrade
the line to incorporate GSM backup. For a 3GSTU-12V any existing alarm pin wiring or power connections can be
re-used. These terminals are in the same relative positions as they are on the 3GSTU. Any existing power supply needs to
be adequate, see page 6. Care must be taken when replacing a 3GSTU-PLI because of the slight differences in the
plug-in connector pin-out (see page 15).
Redcare GSM Connection
redcare gsm requires that the designated ARC be connected to the redcare Digital Services Platform (DSP).
Safety Statement
The circuit board area, under the cover, is classed as a Telecommunication Network Voltage (TNV-3) circuit. All other
interconnection points are classed as Safety Extra-Low Voltage (SELV) circuits. It is only necessary for this cover to be
removed during installation of the PSTN wiring. A protective earth connection is required to the terminal block TB5.
GSM STU EV is designed for host-independent fitment.
The host alarm panel or box into which the GSM STU EV is installed must provide a RESTRICTED ACCESS LOCATION and a
FIRE ENCLOSURE in accordance with the requirements of BS EN 60950.
It is essential that the GSM STU EV is installed so that there is a gap of at least 5mm between it and any other part of
the host equipment (excluding the mounting face). If any part of the host apparatus uses or generates voltages in excess
of 250 V rms or dc, obtain advice from a competent telecommunications safety engineer before you install
the GSM STU EV.
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Siting
When surveying the site please remember that the GSM STU EV operates in a
similar way to an ordinary mobile telephone, therefore any restrictions
on the use of mobile telephones in the area will also apply to the GSM STU EV.
Premises such as hospitals, petrol stations, airports, blasting areas etc. may operate
a mobile telephone restriction in certain areas. Always ensure that the chosen site
is free of any mobile telephone restrictions and advise the end user so that they are
aware, should any restrictions come into force in the future.
It is useful to perform a signal strength test during a pre-installation site visit.
This task requires the use of an O2 connected digital GSM mobile telephone.
To perform a GSM signal strength test:
1. Determine where the GSM STU EV enclosure will be eventually situated.
2. Place the phone where the GSM STU EV is to be installed, switch it on and observe the signal strength.
If the signal strength is weak, try to find a better position for the GSM STU EV. If required, higher gain extension
antennas and extension cables are available at extra cost. For further information, contact BT redcare products, telephone
number 08702 400 503.
Power Supply
The GSM STU EV must be connected to a suitable power supply. The installer must ensure that the rating of the power
supply is greater than the combined rating of the GSM STU EV and any other apparatus drawing power from the
power supply.
The GSM STU EV supply requirements are detailed on page 6.
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Line Compatibility
The GSM STU EV is designed for connection to either the Public Switched Telephone Network (PSTN) or a Private Wire
(RedDIRECT). It is also compatible with earth calling lines.
It is NOT to be used with 1+1 carrier systems or a shared service.
The GSM STU EV must NOT share a telephone line with other electronic data equipment, such as a facsimile machine,
EPOS terminal or digital communicator unless a redcare Modem Compatibility Device (MCD) is used.
(MCD cannot be used with Private wire or Earth Calling lines.)
Only one GSM STU EV may be connected to any one telephone line.
REN
The Ringer Equivalence Number (REN) for the GSM STU EV is 1.0. As a guide to the number of apparatus that can be
simultaneously connected to a line, the sum of REN values for each apparatus should not exceed 4.0. A BT provided
telephone is assumed to have a REN value of 1.0 unless otherwise marked. If the GSM STU EV is used with an MCD, the
combined REN will be 1½.
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Installation

Installation
Training Courses
BT redcare offer a free training course for installers of the redcare gsm service. For further information call General
Enquiries Tel: [phone]
Pre-Installation Requirements
Before a GSM STU EV installation can commence, a redcare Service Order must be submitted to BT redcare by the Alarm
Receiving Centre. This ensures that the appropriate exchange connections have been made and a redcare block
terminal 92A has been provided, if required, at the customer’s premises.
CPE Number
The CPE (Customer Premises Equipment) number of the GSM STU EV must match that on the redcare service order
allocated to the premises. The CPE number can be found on the outer GSM STU EV packaging as well as on the
GSM STU EV circuit board itself (see below).
BT redcare maintain a database of the unique CPE numbers matched to the associated PSTN telephone number and the
mobile phone number of the GSM unit. For this reason the SIM card in the GSM unit cannot be changed or used in
any other installation.
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Page 12
Important:
THE ALARM SYSTEM MUST BE TOTALLY POWERED DOWN
(SWITCH OFF MAINS AND DISCONNECT THE BATTERY)
BEFORE INSTALLATION CAN COMMENCE.
For certain alarm panels, the GSM STU EV can be directly mounted using the
"Plug-in" connections available. Locate it on the two 8-way connectors on the
control panel circuit board. Take care to align the pins to the sockets on the
board correctly: if they are out of alignment, damage may occur.
For other alarm panels and installations where “Plug-in” connections are not
available, the unit can be wired “stand-alone”. Ensure that the supplied mounting
blocks and the GSM STU EV base are free from dust or grease. Bond the double-sided
adhesive pads to each side of the blocks as shown, and affix them to the underside of
the GSM STU EV. The assembly can then be fitted onto a clean, flat surface within the host enclosure.
Care must be taken when connecting wires to the main terminal block TB1 and the telephone terminal block TB5.
The small screws can be easily damaged by over-tightening. Wiring connected to terminal block TB1 should be kept as
short as possible to reduce the likelihood of RF pickup.
Connecting the Telephone Line and Earth
The TNV circuit cover of the GSM STU EV should not be removed whilst the unit is connected to the PSTN or
Private Wire network.
Remove the TNV circuit cover from the GSM STU EV.
Use two core telephone cable (type: 1/0.5 mm CW1308) that is not yet connected to the PSTN or Private Wire (PW)
network. Strip back the insulation so that 5 mm of wire conductor is exposed. Position the cable in the plastic base as
shown on page 12. Connect one core to the terminal marked A and the other to the terminal marked B.
Strip back an earth cable (green/yellow, core area greater than 1mm²) so that 5mm of wire is exposed. Position the cable
in the plastic base as shown on page 12 and connect it to the terminal marked
The other end of this cable must be connected to a good electrical earth.
Failure to fit an earth cable will prevent proper operation of the unit and will invalidate the warranty.
Replace the TNV circuit cover and secure in position with the screw.

Take the opposite end of the two core telephone cable and strip back both cores so that 5mm of wire is exposed.
Connect both wires to the redcare block terminal.
WARNING: the block terminal contains telecommunication network voltages.
Please note that it is important to use the correct method of connecting the STU to the BT Block Terminal 92A.
The Block Terminal provides an insulation displacement connection (IDC) block for the incoming phone line.
No connections, other than those made by BT, should be made to this IDC block. The GSM STU EV should be connected
to the screw terminals as shown.
Antenna
Note: The antenna will emit Radio Frequency radiation in the same way as that of a mobile phone.
The antenna provided is a flat type (115 x 65 x 17mm) and must be mounted indoors, on a flat horizontal surface,
sufficiently close that it can be connected to the GSM STU EV. The antenna is self-adhesive and will bond firmly to any
clean, dry and flat surface. Make a suitable hole, (typically 11mm diameter) in the top of the box in which the
GSM STU EV is fitted. Prevent swarf from entering the enclosure as it could cause internal short circuits.
Remove any burrs from the hole, pass the RF cable through it and place the antenna in position. It is advisable not to
bond the antenna onto the box at this stage. Wait until the system has been tested, as it is difficult to remove once
attached.
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Try to route the RF cable away from any other wiring within the box to reduce the likelihood of interference.
Carefully connect the RF cable to the GSM module on the GSM STU EV. The connector is a micro-miniature co-axial
(MMCX) screened type and is easily damaged. The connector has a positive locking device and will
click when correctly mated.
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Mains Fail
If an AC fail signal is provided from the power supply, this should be connected to the terminal marked F on TB1.
Tamper
If a tamper signal is provided this should be connected to the terminal marked T on TB1. The tamper alarm can also be
generated and sent to the ARC if the GSM STU EV itself detects a tamper, such as the removal of the NVM.
Power Connection
As stated at the beginning of the Installation section, the power supply must be totally powered down
(switch off mains and disconnect the battery) before making these connections.
For both plug-in and stand-alone installations, the power must always be provided to the screw terminals at TB1.
The power supply must be arranged such that the GSM STU EV is powered simultaneously to, or before, the alarm panel
to which it is connected.
DAMAGE CAN OCCUR IF THE ALARM PANEL IS POWERED AND THE GSM STU EV IS NOT.
The supply to the GSM STU EV must be provided by hard wiring the TB1 screw terminals to a suitable power
source. Connect +12V to the terminal labelled V+ and 0V to the terminal labelled 0V. This power wiring must be less
than 3m in length and use wires having core areas of at least 1mm2. The GSM STU EV will take a peak current of 350mA
from the 12V supply, when the GSM transceiver is in operation. The current consumption otherwise is typically 160 mA.
Alarm Inputs
For “Plug-in” installation, alarm pin connections are made automatically whenthe GSM STU EV is plugged in to the
host alarm panel. When fitting the GSM STU EV, check that the signals presented by the alarm panel match those
required by the STU, for the two sockets SK1 and SK2. The pins have been designated the following functions on
the GSM STU EV:
For plug-in installations, be sure that no wires are ever connected to the terminals 1 to 8 on TB1. Terminals 9, T & F
can be connected if these channels are required in addition to those present on the plug-in connectors (SK1 & SK2).
For stand-alone installations, alarm input terminals on terminal block TB1 must be connected to the alarm panel outputs.
Unused channels can be left unconnected.
The TB1 terminal marked is reserved for GSM failure, and the ATS Test function in accordance with BSIA form 175.
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Note: If ATS Test is used by the panel on the plug-in connector, it must be linked to alarm 8 using the jumper at LK3 in
position P11.
Terminal Block TB1 Alarm Channel Configuration
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SK1 Function SK2 Function
Pin 1 Alarm Input 1 Pin 9 Not Used
[+12V on 3GSTU]
Pin 2 Alarm Input 2 Pin 10 Signal Ground
[0V supply on 3GSTU]
Pin 3 Alarm Input 3 Pin 11 ATS Test (via LK3)
Pin 4 Alarm Input 4 Pin 12 Not Used
[+5V on 3GSTU]
Pin 5 Alarm Input 5 Pin 13 Alarm Input 6
[5 or 7 on 3GSTU) [Not used on 3GSTU]
Pin 6 Tell Back (output) Pin 14 Alarm Input 7
[Control Output on 3GSTU [Alarm 6 on 3GSTU]
Pin 7 Comms Fail (output) Pin 15 Line Fault (output)
[Not used on 3GSTU]
Pin 8 Low battery (input) Pin 16 Alarm Input 8 via LK3
Chan. No. TB1 Ident Function
1 1 Fire
2 2 Hold Up Alarm
3 3 Intruder
4 4 Opening / Closing
5 5 Zone Omit
6 6 Optional
7 7 Confirmed
8 GSM fail / ATS Test (reserved)
9 9 Optional
10 10 ATS GSM Test (reserved)
11 11 ATS Landline Test (reserved)
12 T Tamper
13 F AC Fail

Plug-in Compatibility Link (LK3)
Some newer alarm panels use pin 11 as the ATS Test function on the plug-in connectors, whilst older panels may use pin
16 as alarm 8. GSM STU EV is supplied with an NVM (IC10) programmed and fitted to enable ATS Test mode
(see page 18). The jumper, at LK3, is fitted as supplied, to enable compatibility with plug-in panels using the ATS test
feature (SK2, pin11 connected to pin alarm 8 for ATS test).
Set the jumper in the lower position for use with older plug-in panels that use SK2, pin 16 as alarm 8. For stand-alone
(wired) installations the setting is irrelevant.
Output Relays
Three output relays are provided: Control, Return Path Signalling (RPS), and Line Fault.
Note: If an output is to be connected to a device which produces transient voltages, such as a bell, the device should be
suppressed using a suitable protection diode. Each relay’s contacts (Normally Open, Common, Normally
Closed) are available for connection on terminal block TB1. The relay contacts have a maximum current rating of 1 Amp.
GSM STU EV can be programmed to indicate communications path failures in different ways. Available options include
the Line Fault Relay indicating that both paths have failed (default); the Line Fault Relay indicating that one of the two
paths have failed; or landline and GSM path failures may be indicated on a combination of two of the three available
relays. These alternative modes of operation are not suitable for a GSM STU EV used as a plug-in.
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Control Output
The Control Output can be used as a general purpose output which is controlled by the Alarm Receiving Centre. It may be
used for various functions including the remote resetting of alarm panels. Additionally, this relay can be used in
conjunction with the Line Fault relay to indicate discrete communication path fails at the protected premises (in this
mode, the Control Output relay is no longer controlled by the ARC)
For plug-in installations, Control Output connections are made automatically when the unit is fitted in the host alarm
panel. The host alarm panel must be programmed to enable this function (TELL BACK).
Return Path Signalling Output (RPS)
The RPS output is used to indicate, at the protected premises, that the opening/closing signal has been sent to and
acknowledged by the Alarm Receiving Centre.
To use the RPS function, one of the alarm inputs must be designated as an opening/closing channel (usually channel 4).
The RPS output will activate when an opening or closing signal is detected. It will de-activate when the opening or
closing signal has been acknowledged by the Alarm Receiving Centre. It is allowable to have more than one input
designated as an opening/closing channel, but each must be acknowledged to de-activate the RPS output.
To use this option, a warning device such as a piezo bleeper or external strobe light should be connected as shown below.
The maximum current rating of the relay contacts is 1 Amp.
Line Fault Relay
The Line Fault Relay is used to indicate, at the protected premises, that one or both, the GSM and landline (PSTN or
Private Wire) communication paths have failed. For plug-in installations, Line Fault connections are made automatically
when it is fitted into the host alarm panel. The host panel must be programmed to accept this function.
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ATS Test
The GSM STU EV is supplied with an NVM fitted, which enables the Alarm Transmission System test function. The ATS test
function allows the alarm panel (and ARC) to distinguish whether one or both paths have failed in the event of a
communications failure. The Line Fault signal (SK2 pin 15 or the Line Fault relay), and the ATS test signal (SK2 pin 11 or
Alarm Pin 8 on TB1) are used in accordance with BSIA form 175. This is available free of charge from the BSIA or
downloadable at:
http://www.bsia.co.uk/pdfs/Form_175.pdf
The alarm panel must also conform to this standard for the function to work correctly. The alarm panel can request an ATS
test by applying the ATS Test signal, the GSM STU EV then communicates with the ARC on both the GSM wireless path
and the landline. If no communication path faults are detected by the GSM STU EV, the ARC will receive a pin alarm 10
over the GSM path and a pin alarm 11 over the landline. When reset, these will complete the end-to-end test.
If the alarm panel asserts the ATS test pin/channel during a line fault the GSM STU EV will signal to the alarm panel
whether it is a dual path or single path failure in accordance with BSIA form 175, using the line fault output and relay.
To deactivate the ATS test function, the plug-in NVM can be carefully removed or re-programmed to suit (see page 21).
For plug-in panels, LK3 may also have to be changed (see page 17).
Telephone Line Selection (LK1)
The GSM STU EV is supplied ready to connect to the Public Switched Telephone Network (LK1 is not fitted).
If the GSM STU EV is to be connected to a Private Wire (RedDIRECT) a suitable link must be fitted in the position marked
LK1. An NVM chip must be configured for PW use and fitted in accordance with the procedure on page 21.
If you have any doubts about the type of telephone line to which the STU is being connected,
contact BT redcare for advice.
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