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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