GEC PKS 2 - Masterline

APPROVAL No. S/1209/3/H/452512 (616) and S/1209/3/H/452513 (1236 & 2464)

Distributed by GEC and later, GPT.  Also sold  by Telephone Rentals as the Trinity.

Terminals to the right are the 1236 standard and executive.

The PKS2 816, 1236 and 2464 key telephone systems employ stored program control and feature a wide range of intercommunication facilities. Many of the facilities can be configured and allocated to stations (extensions) by system programming to suit individual user applications.

All systems in the PKS2 range consist of central equipment to which keystations and other types of stations are connected radially. Trunk lines connect the system to the public switched telephone network (PSTN) and/or PABX.

PKS2 816 systems cater for a maximum capacity of 8 trunks and 16 stations.

PKS2 1236 systems cater for up to 12 trunks and 36 stations but can be increased in capacity by the addition of a 2464 extender unit.

PKS2 2464 systems consist of a combined 1236 base unit and 2464 extender unit and have a maximum capacity of 24 trunks and 64 stations.

The central control unit for the 816 system has a built-in power supply. A separate power supply unit provides power for 1236 and 2464 systems.

Three types of keystation are available for connection to PKS2 system:

Standard keystations have a key and lamp for each trunk, dedicated facility keys, ten DSS/repertory keys and a dial keypad. A built-in microphone and loudspeaker enable intercom 'voice calls'. Special versions are available with any combination of; handsfree (loudspeech) operation on trunk calls, two-colour trunk lamps and/or inductively coupled handset receiver for a deaf aid.

Executive keystations have the same features as the standard keystation but, in addition, have a liquid crystal display that shows the date/time/dialled numbers and associated keys to enable call duration timing and alarm clock functions. Full handsfree operation on trunk calls is provided and special versions are available for bothway operation over a trunk under power fail conditions.

Basic keystations have a single trunk key/lamp, fewer facility keys than the standard keystation and no DSS keys. A built-in loudspeaker enables 'voice announcing' of intercom calls but the basic keystation has no microphone.

Ordinary telephone stations can be connected to the PKS2 system and are able to take and answer calls and use a limited range of facilities.

Special door phone units can be connected to provide handsfree inward calling to specified keystations.

The facilities provided by the PKS2 are listed and described in section 2 and the equipment and its configuration are detailed in section 3 of this manual.

Trunk Data
When a trunk is connected directly to the PSTN, the line loss should not exceed 10db.

When PKS2 Trunks are connected to a PABX and PSTN calls made via the PABX the line loss between the PABX and PSTN should not exceed 8db

Dialling: DTMF or LD dialling.
Disconnect pulse speed and ratio is 10pps/33% make.

Power feed: Under normal operation power for the trunk call speech path is derived from the PKS2 system power supply.

Under power-fail conditions, power for the speech path of dropback stations is derived from the PSTN or PBX.

The ringer equivalence number for each trunk is 3.

Power Supply
Mains Voltage range: 225 to 270V AC - 50Hz

Power Consumption:
816 system - 160W max.
1236 system - 250W max.
2464 system - 490W max.

Mains plug fuse rating:
816 system - 3A
1236 system - 5A
2464 system - 5A

					816		1236/2464
					system		system

Power unit fuse ratings: Mains input	1.0A		4.0A	20mm glass
			 30V output	2.0A		10.0A	20mm glass
			 20V output	1.6A	     F2 3.0A	20mm glass
						     F3	2.0A
			 12V output	0.3A		0.5A	20mm glass
			 5V output	1.6A		6.3A	20mm glass

Central unit sizes
		      h		w	    d	    Weight fully equipped
816 control unit:   31Omm  x  54Omm   x  25Omm		19Kg

1236 control unit:  41Omm     540mm      23Omm		20Kg

2464 extender unit: 41Omm     54Omm  	 230mm		16Kg

1236/2464 PSU	    210mm     54Omm 	 23Omn		18Kg

Station line limits

                   Maximum           Maximum
Station type:      line loop         Cable length            No of wires:
		   resistance	     0.5mm  0.67mm

Keystation	   50 ohms	     300m   500m	     4-wire
							(Two twisted pairs)

POT		   50 ohms	     30Om   500m	     2-wire
Doorphone						(Twisted pair)

DSS Console	   25 ohms	     150m   250m	     2-wire
							(Twisted pair)

Operating environment

Operating ambient temperature range,
control unit and keystations:			Oc to 45c

Storage ambient temperature range:		-20c to 70c

Humidity range:					10% to 95% non condensing

LJU Wiring

LJU 2/3C Wire colour MDF termination
3 Blue/White 2
5 Orange/White 4
2 White/Orange 3
4 White/Blue 1



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Last revised: November 05, 2021