Section II. PATCHING OPERATIONS - TM-11-5895-878-14-P0090

TM 11-5895-878-14&P

controller has access to all circuits entering or leaving

and receives from the relieved technical controller a list

his station by means of the various jackfields in the

of tasks, arranged in order of priority, which were not

patch and test areas. Test equipment is provided in the

completed during the preceding shift. The relieving

test bays. to permit measurement. of levels and circuit

technical controller proceeds with the accomplishment

quality. In the course of his duties, the technical

of these tasks. When a task is completed, the next

controller frequently has a need to coordinate with, or

highest priority task is started, or if the list is completed,

assist, maintenance personnel. This requirement occurs

routine monitoring of circuits is begun. Any alarm, or

during trouble isolation, patching out equipment for

other precedence item, interrupts the routine activity of

maintenance, test and analysis, and other similar tasks.

the technical controller. Precedence occurrences are as

follows:

b. Tasks. The technical controller has, as his

responsibility, tasks which are routine, as well as priority,

(1) Equipment alarm.

in nature. A task list is maintained by the technical

(2) Signal alarm.

controller. Priorities of tasks are assigned, and are

(3) Request for an on-call patch.

accomplished. in order of priority. Precedence work

(4) User complaint.

tasks may develop from equipment alarms, signal

(5) Request for assistance from a distant

alarms, fuse alarms, on-call patch, requests from distant

technical control.

controllers, user complaints, direction from higher

authority, or return of equipment from maintenance.

(6) Direction from a higher authority.

The tasks of the technical controller are categorized as

(7) Completion of maintenance activity.

follows:

d. Coordination.

The technical controller

(1) Assign priorities to work task in

investigates all user complaints, cooperates with other

accordance with circuit priority and action precedence.

technical controllers in rectifying troubles, and in the

(2) Monitor

station

equipment,

circuit

case of problems affecting service, keeps the users

performance and act on alarms.

informed of the status of their circuits. A considerable

amount of coordination is required between the

(3) Evaluate circuit/equipment status.

technical controller and station maintenance personnel.

(4) Coordinate with. users, other technical

In-station patching during trouble isolation, release to

controllers, maintenance personnel, and investigate any

maintenance, return from maintenance, equipment

other factors affecting service.

substitution, and other similar activities requires

(5) Test and analyze equipment/circuit

cooperation among operators and maintenance,

capability.

technicians. Use of the jackfields and test instruments,

(6) Substitute

facilities/alternate

route

located in the patch and test area, for monitoring and

circuits.

testing very often requires the assistance of the

(7) Record status.

maintenance technician to set up the test and analyze

the results. Procedures for patching operations, testing

(8) Report status to affected parties.

and monitoring, and some examples of each are

(9) Restore facilities after maintenance or

described in the following paragraphs.

testing.

c. Order of Priority. The technical controller, at the

start of the shift, reviews the previous shift log entries

Section II. PATCHING OPERATIONS

3-5. Purpose of Patching

and/or channels usually locates the fault. Often, it is

Patching is defined as the rearrangement of the

possible to patch out all station equipment is one

electrical interconnections among items of station

patching operation, establishing quickly whether the

equipment by means of patchcords and jackfields.

fault is in any of the local station's equipments. Once a

channel or equipment has been patched out, test

a. Service Restoration.

The various patching

equipment is employed to evaluate circuit performance

facilities provided in the station technical control area

and to localize the fault.

enable the technical controller to take positive action to

restore service when a circuit failure has been localized

c. Service

Continuity

During

Maintenance.

to his station. Such restoration action consists of

Preventive maintenance routines require periodic quality

bypassing the defective equipments and substituting like

control tests (section V) and adjustments of channels

equipments from the complement of operational spares

and station equipment. When it is necessary to conduct

and, similarly, substituting spare, or lower priority,

such tests on assigned channels or equipments, service

channels for those degraded or inoperative.

The

maintained

patching

substitution.

substitution of equipment usually involves only a local

Troubleshooting and corrective maintenance (section III)

patching operation, while substitution of channels

requires that the defective equipment be disconnected

requires a coordinated patching operation at the distant

from the circuit and a spare substituted.

This

terminal.

substitution is accomplished by patching.

b. Fault Isolation by Substitution, Substitution of

d. .Operational Spares.

Operational spare

station equipment and channels by patching operations

facilities consist of spare multiplex channels and

is a valuable fault isolation technique.

A logical

selected items of equipment cross-connected into

procedure of successive substitutions of equipment

specific spare configurations.

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