BT ENSIGN 1 & 2


PXML No. 71
APPROVAL No. S/1000/GF/1981/PR

Programming Guide
User Guide


Ensign was sold by British Telecom, but was made manufactured and marketed by TMC Ltd (Malmesbury, Wilts) as the KBX10.  Was later known as the Merlin S3012.

Ensign may be installed for use as either a PBX or KEYSYSTEM, and in its basic form has a capacity of 2 external lines (MF or LD) and 4 extensions (2 + 4). Add on units can be supplied which allow the system to grow in stages, so as to suit the customers required mix of extensions and external lines. The system has a maximum of 12 ports and can be configured by building in 2 port cards to a maximum configuration of 6 exchange lines/6 extensions and a minimum of 2 exchange lines/10 extensions.

The distribution cables are 4 wire, divided into speech and data pairs and are terminated upon either standard 2 wire POTs (LD only) or, 4 wire Telephones 4/SA 20000 type (HS Herald Terminal). 4-wire terminals use a speech pair (A and B) for transmission of speech, line supervision and the powering of the tone caller and a data pair (C and D) for signalling of lamp (L.B.D.) data to the terminal, signalling keyed numbers to the central unit and powering of non-speech circuits. The terminal's non-speech circuits are constant-current fed.

In the event of a mains power failure two exchange lines are automatically switched through to special 'power-fail' ENSIGN terminals or standard 2-wire telephones without the loss of calls in progress. The system restarts automatically when mains power is restored.

The control unit is wall mounted and is cooled by natural convection.
At a later date a new style terminal called the TX33 was introduced for Ensign, this was similar looking to the SDX range of FT telephones.
The data pair is not connected on 2 wire telephones.  The system will automatically recognise an Ensign Terminal when wired correctly.

Feature phones supported
Tele 4/SA20012 Standard Terminal (Brown or Grey) - old style Herald phones.
Tele 4/SA20014 Standard Power fail Terminal (Brown or Grey) - old style Herald phones.
TX33 Low Profile Terminal with monitor (Grey or Beige) - Viscount style telephone.
TX55A Modern Terminal with monitor (Beige, Stone or Grey).
TX56A Modern Terminal with Handsfree (Beige, Stone or Grey).


PARTS LIST


SYSTEM NUMBERING (DEFAULT)
0 Operator
1 Cancel ring when free
2 Ring-when-free
3 Three party
40 Recall parent PABX
41 Divert calls
42 Cancel diversion of calls
44 Repeat last number
50-59 Store Rep. Calling Nos.
60-69 Call Rep. Calling Nos.
9 Outgoing line access

CONFIGURATION
The Ensign is initially supplied as a 2+4 system. Three additional cards may be fitted in the empty frame. These cards, 2+0 (2 trunks), 0+2 (2 extns) and 1+1 (1 trunk & 1 extn) must be fitted in a certain manner.

1. Trunk cards (2+0) can only be installed in the top two spaces
2. Only one 1+1 card can be in the system and this must be in the top or middle spaces and follow trunk cards.
3. Extension cards can be fitted to any slot but must follow 2+0 or 1+1 cards, if fitted.

From the above it follows that the configuration can be 2+4, 6+6, 5+7, 4+8, 3+9, 2+10. A maximum of 12 ports.

The software is configured by means of a bank of switches beneath a plastic cover on the front of the unit. System operation is dependant on how the switches are set.

Software versions are 4.1 and 4.2.


CONNECTIONS
A local signalling earth should be run to SK2 on the distribution unit. (this will be a bunched 0.5mm cable). SK1 is the earth connection for the POT's.

4 WIRE TELEPHONE SOCKET WIRING USING A LINE JACK -/3A)

System Colour Socket
A WHITE/Blue 5
B BLUE/White 2
C WHITE/Orange 4
D ORANGE/White 3
 

2 WIRE TELEPHONE SOCKET WIRING USING A LINE JACK -/1A)

System Colour Socket
A WHITE/Blue 5
B BLUE/White 2
Earth WHITE/Orange 4

2-Wire telephone
Telephones No. 8746GR should be installed as these telephones are fitted with a Switch No. 5A wired in a non-standard manner.  This switch is the recall switch.
To fit a Switch No. 5A into an ordinary Telephone No. 8746:
1. Green of the telephone cord and blue of the Switch No. 5A is connected to T15.
2. Slate of the Switch No. 5A is connected to T8.
3. Brown of the Switch No. 5A is connected to T14.

EXTENSION LINE LIMITATIONS
TX33 TERMINAL 1.5Km 266 ohms
HS TERMINAL 2.6Km 510 ohms
2w TELE 5Km 1200 ohms

PROGRAMMING
Programming is solely by the use of a bank of DIL switches located behind the slide on screw cover located on the front.  The system is dependant on how these switches are set and the tables below explain the different settings.  The "0" in the tables represents the position of the DIL switch.

Changes to the configuration switch settings are not effective until the run/park switch has been reset from park to run.  The picture below explains the functions of each DIL switch and advises of the types of switches that may be found..

Trunks
To set number of trunks and ringing type, set the System Switch as required.  The system will operate to automatic or manual ringing on incoming calls, and all lines must be of the same type.

1 Line fitted   2 Lines fitted   3 Lines fitted   4 Lines fitted   5 Lines fitted   6 Lines fitted
M     0   M   0     M   0 0   M 0       M 0   0   M 0 0  
A 0 0     A 0   0   A 0       A   0 0   A   0     A     0

The table above shows how the System Switch is set for the type of ringing and the number of lines.
M = manual ringing (plug type switchboards etc)
A = automatic ringing

Trunk parameters are set on an individual basis. Please refer to the table below for the settings of each trunk.

MF 4 REGISTER RECALL IN DIAL 9 GROUP IN ANS EXCH GROUP
LOOP/DIS EARTH RECALL OUT DIAL 9 GROUP OUT ANS EXCH GROUP

Extensions
Ensign Press Button Telephones
The tables below show the pack number, facility name, configuration switch setting, and key layout of a 1 /SA 20000 type Ensign telephone. Each pack provides set facilities. The top 6 keys are the keys to the right of the keypad, whilst the remaining 2 are those beneath the keypad.

2-wire Telephones
2-Wire telephones are given the same pack numbers; they have the 'Dial-Up' facilities, but have no press-button facilities except for PBX recall.

Packs
E/L O/G access from a 2-wire telephone is dial 9 for all packs.

E/L I/C calls are answered at a 2-wire telephone according to pack allocation as follows:-
Packs 1, 2 & 3: Off-hook to all lines in the ANS/EXCH group only, barring as per diagram.
Pack 5: 0ff-hook to all lines connected to system.
Pack 6: as 5 with call barring.
Pack 7: as 5 with International Call Barring.
Pack 8: 0ff-hook to all lines in ANS/EXCH group only - no calls barred; pack 8 also has DIAL TONE TRANSFER and may be used for an operators position.
Packs 9, 10 & 11: NO ACCESS to I/C Exch. calls except by transfer from operator. Call barring as per diagram.
Pack 12: Exclusive off-hook to line 1.
Pack 13: Exclusive off-hook to line 2.
Pack 14: Exclusive off-hook to line 3

Note on Packs 12, 13 & 14:- Exclusive only if packs 5, 6, 7 or 12 are not allocated to any other extensions and if line is OUT of the ANS/EXCH group - otherwise snared with those packs and ANS/EXCH Users.) Pack 15 with system switch set for 1 line - Off-hook to lines 1 only, when that line is under diversion.

Pack 15 with system switch set for 2 lines - Off-hook to lines 1 & 2 only, when those lines are under diversion.
Pack 15 with system switch set for 3 to 6 lines - Off-hook to lines 1, 2 & 3 only, when those lines are under diversion.

Note on Pack 15:- If packs 12, 13 or 14 are not allocated to any extension then off-hook access to pack 15 users is available at all times on lines 1, 2 or 3 respectively.

THE DIAGRAM NUMBER IS THE FACILITY PACK NUMBER TO BE CHOSEN FOR THE EXTENSION AND IS ALSO THE NUMBER OF THE LABEL FOR A 1/SA20000 TYPE TELEPHONE IF FITTED AT THAT EXTENSION.

The figure after the dot in packs 5 & 15 is the number of exchange lines to be set on the system switch. On systems with 4 or more exchange lines Pack 15.3 is always allocated for pack 15. The configuration is automatically altered when the system switch is set for the number of exchange lines.

In all the switch diagrams, '0' in the upper row indicates that the sub-switch is to be moved to the ON position, and '0' in the bottom row that the sub-switch is to be moved to the OFF position. Slide switches are UP for ON, rocker Switches are pressed IN at the TOP for ON. In the case of system Switches and exchange line switches the required parameter is selected by moving the subswitch in the direction indicated.

1 ACD 2 ACD 3 ACD 5.1 K&L 5.2 K&L 5.3 K&L
      0       0         0 0      0   0      0   0      0   0
0 0 0     0 0   0   0 0        0   0      0   0      0   0  
T20
T21
T22
T23
3 PARTY
ANS EXCH
As 1 but
with
Call
Barring
As 1 but
with
International
Call
Barring
L1
T20
T21
T22
T23
T24
L1
L2
T20
T21
T22
T23
L1
L2
L3
T20
T21
T22
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder

 

5.4 K&L 5.5 K&L 5.6 K&L 6 K&L 7 K&L Operator
  0   0     0   0     0   0     0      0 0    0  
0   0     0   0     0   0      0    0    0        0
L1
L2
L3
L4
T20
T21
L1
L2
L3
L4
L5
T20
L1
L2
L3
L4
L5
L6
As 5.1 to 5.6  but
with
Call
Barring
As 5.1 to 5.6
but
with
International
Call
Barring
T20
T21
T22
NIGHT SER
REVERTED
ANS EXCH
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder

 

9 PBX 10 PBX 11 PBX 12 EXEC 1 13 EXEC 2 14 EXEC 3
0     0   0   0     0   0 0   0 0 0    0 0 0 0    0 0 0
  0 0       0   0     0            0  0        0         
T20
T21
T22
T23
Redirect
3 Party
As 9 but
with
Call
Barring
As 9
but
with
International
Call
Barring
L1
T21
T22
T23
Redirect
3 Party
L2
T20
T22
T23
Redirect
3 Party
L3
T20
T21
T23
Redirect
3 Party
Monitor/
Speak
Monitor/
Speak
Monitor/
Speak
Monitor/
Speak
Monitor/
Speak
Monitor/
Speak

 

15.1 SEC 15.2 SEC 15.3 SEC 0 = OOS Pack Number
0 0 0 0   0 0 0 0   0 0 0 0                   
                               0 0 0  0         
L1
T20
T21
T22
T23
3 party
L1
L2
T20
T21
T22
3 party
L1
L2
L3
T20
T21
T22
Extension
not Fitted
or Extension
out of
Service
6 Buttons
on
Ensign
Telephones
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Monitor/
Sounder
Buttons
below keypad

The Monitor button is only effective when an Amplifier  No. 13 is also fitted in the Ensign telephone.
The Call/Clear button is only effective when a Jack Unit No. 4A is fitted and a headset used.


COMMISSIONING THE INSTALLATION
STAGE 1
A battery is provided to maintain information in the repertory dialling stores in the event of mains failure, but it is usually disconnected whilst Ensign is in store so that it does not become discharged. To connect the battery locate the LKF link on the processor board (towards bottom centre) and place the U Link which has been placed on one of its pins across them both.

STAGE 2
Check that the 250V mains lead is clipped into position down the left hand side of the cabinet and that the rubber grommet it passes through at the bottom of the base is in position. Cut the free end of the mains lead to the required length and connect a mains plug fitted with a 3 amp fuse.

STAGE 3
Check that all ribbon cables have been plugged in securely and that their latches are in position.

STAGE 4
Close and latch the 2 hinged frames, and then fit the metal cover retaining bracket. Record details of the installation on the Card and then place the card inside the cover before fitting it into position.
Leave the Ensign label off until commissioning is complete.

STAGE 5
Set the RUN/PARK switch upwards to the PARK position.

Plug-in and switch on.
There will be a short delay whilst the system powers up, on the successful completion of which, the LED will glow continuously. The system is now fully prepared for service but is PARKED, preventing any calls from being made.

If the LED remains off, check the mains connections.
If the LED flashes, the switch may not be in the PARK position; switch off mains supply reset RUN/PARK switch and try again. If still unsuccessful refer to the maintenance section of the Ensign manual.

STAGE 6
To bring the system into service from Stage 5, set the RUN/PARK switch to the RUN position. There will be a short delay whilst the system reads the configuration switches and performs a test routine (up to 30 seconds) then the LED changes and flashes twice a second.
The system is now running and ready for service.

LED INDICATION
If the flash rate 'SHORT-ON', 'LONG-OFF' appears there is a configuration error. Check configuration switch settings, and that the correct type of add-on units have been fitted.

If the flash rate 'LONG-ON, SHORT-OFF' appears the processor test routine has detected a fault. Switch off the power and make another attempt repeating

STAGE 7
If still unsuccessful refer to the maintenance instructions.

LED States
Rapid even on-off - System running ok.
Permanently on - Waiting to PARK or PARKED waiting to run.
Long on/long off - International call barring digit count maximum accepted
Short on/long off - Configuration error
Long on/short off - Memory or processor error
Off - Parked or no power.

Power Supply Voltages and Fuses
The power test points are situated at the right hand bottom edge of the Processor board just above the Power connector.  Two fuses can also be found to the left of these test points.  The fuse rating is 250mA and they protect the ringing supply.
The TMC type power supply is also fitted with a 1.6A fuse.

Rail -50v +44 0 +5 -12 +5 +1.5 +12
Tolerance +/- 10% - 20% 0 +/- 5% +/- 5% +/- 5% +/- 10% +/- 5%

KNOWN PROBLEMS

  • Diverts on extensions appear if by magic. User did not dial 9 for outgoing call and inadvertently set a divert.
  • Power unit failures. Any system left on the shelf should be powered up on a regular basis. Capacitors in the PSU tend to go S/C if left unpowered for long periods of time.
  • Due to construction of the Ensign the PSU gets hot and can possibly fail. A good cure is to install a small low voltage fan in the top of the case. The 12v supply can be used as power source! This is not approved.
  • System looses memory after power fail. Generally due to a flat battery or run/park switch in wrong position - check battery voltage and replace if voltage is not as specified.
Ensign with cover in place (left) and with switch cover removed (right)
The cover is removed by sliding it sideways and the two screws underneath are then removed.
 
Removal of the cover exposes a metal retainer
Push both retainer sides inwards and the retainer can be removed
 
 
The gates can now be swung open
 
The first gate can hold three option cards
 
This is the power supply, processor card and distribution frame (top right)
 
Close up of the PSU.  If kept as spares they should be powered up on a 6 monthly,
as the capacitors blow
 
The second gate holds the 2+4 card
 
Close up of three option cards
 
 
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Last revised: October 30, 2022

FM