Melvin Price L&D, Alton, Illinois

APPENDIX B: FIELD VISITS TO CORPS LOCK AND DAM PROJECTS

Ice Harbor Project, Pasco, Washington

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tomated system, and to discontinue the use of the

The Marseilles lockmaster's opinion is that the

manometer gages. The cost was estimated to be

remote dam operation is a valuable asset, but

,000.

that the automation part of the system is exces-

There is not an entirely satisfactory procedure

sive and unnecessary technology. With the unre-

for servicing or solving problems with the sys-

liability of upper gage readings, he believes that

tem. Although there is a technical contact in the

the automation system could actually prove to be

District office, the lockmaster does not think the

dangerous.

technical familiarity with the automated equip-

ment at the District level is any better than his

Melvin Price L&D, Alton, Illinois

own. The lockmaster at Lockport Lock upstream

This Mississippi River project is quite new,

has been able to provide some technical assis-

built in recent years to replace the failing Lock

tance to the Marseilles crew, since there is some

and Dam No. 26 located about two miles up-

similar equipment on the upper lift-type gate at

stream, and it was designed to have modern

Lockport. In general, however, the Marseilles

automated control technology. The site visit on

lockmaster has been on his own to troubleshoot

23 July 1991 was hosted by an electrical engineer

or repair the system, and he is able to replace mi-

from the St. Louis District, who conducted a thor-

nor components. A new electrician had joined the

ough tour of the project and demonstrated the

crew shortly before the visit, and this man had

automated systems. This engineer came to the

experience with automated industrial control

Corps after the system at Melvin Price was de-

equipment, so the lockmaster was familiarizing

signed and specified, but he had been closely

him with the system as much as possible.

involved with inspecting the system during con-

The lock crew has no users' manual or trouble-

struction and installation, working out the rela-

shooting guide, because none were provided as

tively few problems with the system since

part of the contract. When problems cannot be

completion, and modifying the system as actual

solved, the manufacturer of the components is

operating experience dictates.

called, and while there is no service or mainte-

The extensively automated project offers lock-

nance contract, a technical representative is avail-

house control of all tainter gates, filling and

able within 72 hours--usually much sooner. The

emptying gates, miter and lift gates, etc. The

manufacturer's technical representative has been

automated control system at Melvin Price is

out a few times, but the undependable upper

made up of sensors of various types (e.g., limit

gage problem remains. If the system were to be-

switches, inclinometers on tainters, etc.), "cards"

come totally inoperable, the lockmaster could sta-

in input/output (I/O) boxes (or panels) at each

tion someone in an overtime status at the dam to

controlled device, cables (two four-strand cables

operate the facility manually.

linking each I/O box with the central computer),

Some problems have been encountered with

programmable logic controllers (PLCs), and the

weather effects on components: high tempera-

central computer.

tures in input/output (I/O) boxes on each dam

Any changes to operational procedures that

gate pier, water leakage into cable connections,

are to be controlled by the system are made by

etc. The lockmaster is also concerned that exces-

modifying the programs in the PLCs. The lead

sive temperatures occur in large control boxes at

electrician on the lock crew can program PLCs on

the dam and at the lockhouse; he has wondered if

site, or the electrical engineer can program the

there should be artificial cooling for these compo-

PLCs from his office at District headquarters via

nents.

modem. In fact, one could program/reprogram

There are three remote TV cameras at the dam

or operate any part of the automated system

that allow remote observation of the dam on

from anywhere in the District or even the coun-

monitors at the lockhouse. However, these can-

try via modem.

not be used to verify gate operation. A short time

The system of PLCs has never given any prob-

earlier the lock crew had installed a staff gage

lems, but individual sensors have given a few

that can be seen by one of the cameras, and is

problems. If a new operation or function is need-

readable to a tenth of a foot. So far the cameras

ed, all that is required is to install a sensor, limit

have given satisfactory performance, except

switch, or whatever device is needed, and then

when their video tubes have been destroyed by

run wires to the nearest I/O box. There is never

excessive light (such as sunlight reflected from

any need to string new cables back to the lock

the water).

operations building. The operation or function

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