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C.B. CORD P.B.X. WITH AUTO OR MAGNETO EXCHANGE LINES
TYPE N326
INDICATOR SIGNALLING
The N326 switchboard provides simple P.B.X. facilities with the minimum amount of equipment. It can be installed as a single unit, or two units
together to form a two-position non-multiple switchboard. Exchange lines are normally for connection to an
automatic exchange but, alternatively, can be magneto.
FACILITIES
1. Through dialling and through clearing.
2. Separate negative supervision on local calls. Double negative supervision on exchange calls.
3. Visual ringing indication.
4. Operator re-call on local and incoming exchange calls.
5. Ring back.
6. Night service on cord circuits 1 to 11.
7. Audible alarm.
8. Cord test.
9. Safeguard of exchange service on mains failure.
CONSTRUCTION AND FINISH
Information on the construction and appearance of the boards is given on page 17.
The equipment has full tropical finish; i.e. coils ate impregnated and metal parts specially finished. The dial mechanism has a plastic cover. Wire conductors are insulated with p.v.c. which is
moisture-proof and not subject to fungoid growth or attack by insects.
CAPACITY, WIRING AND STOCK EQUIPMENTS
Type
|
Exch line
Capacity |
Exch line
Wired |
Exch line
Equipped |
Extn Lines
Capacity |
Extn Lines
Wired |
Extn Lines
Equipped |
Cord Ccts
Capacity |
Cord Ccts
Wired |
Cord Ccts
Equipped |
| N 326 |
20 |
10 |
10 |
100 |
70 |
50 |
17 |
15 |
10 |
| N 326 |
20 |
10 |
10 |
100 |
100 |
70 |
17 |
15 |
12 |
APPARATUS
Keys ate N9300 miniature type with wedge handles having inserts of contrasting
colours in the tips so that an operated key is instantly discernible.
Totally enclosed miniature twin-shutter indicators are used. Those in the left-hand panel display a black figure against a pink ground; those in the right-hand panel a black figure against a green ground. The labels of the associated jacks in the centre panel are similarly coloured to assist line identification.
Extension line indicators N483l are non-locking and self-restoring. Exchange line indicators N4833 operate and lock via a second winding and are automatically restored when the answering plug is inserted.
Relays and battery feed retards are Type N30000 (B.P.O. 3000).
The dial has standard numbering, a 2:1 break: make impulse ratio, and a p.v.c. shroud round the mounting, as well as a plastic rear cover.
A rotating-magnet hand generator is fitted as standard, but power ringing from any available external source can be connected. See also Alternative (3).
Connecting cords have p.v.c. insulated conductors, a p.v.c. sheath and a polypropylene braid over all. If the standard provision for night extension on cord circuits 1 to 11 is insufficient, plug-ended 'through' cords can be supplied to connect extra circuits.
A modern plug-in lightweight handset with rocking-armature receiver and coiled p.v.c. insulated cord is supplied.
POWER DETAILS
Nominal operating voltage: 24 volts d.c. Busy hour current drain: 2 amps.
DIMENSIONS
Width - 31in
Height - 48in
Depth - 32in
WEIGHT
50 line - 244lb
100 line - 259lb
ALTERNATIVES (Supplied to Order)
1. Dial with any desired numbering or impulse ratio.
2. Magneto exchange lines.
3. Transistor Ringing Unit in lieu of, or as well as, the hand generator.
4. Lightweight headset in lieu of, or as well as, the handset.
ORDERING INFORMATION
Specify the Type No., number of lines and any of the Alternatives required.
The N326 was made obsolete in 1971 and
replaced by the N327.
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