: AVN) 0-00 Med Aol atolo) (SM Natel ms )avolt] (ofl s{-M .<-Yovolde(-YoMolimsiia) Ml @lilolary 
Variable 
Reactor Core 
No. of Points 
Variable 
No. of Points 
Coolant flow in main-coolant piping 2 
Bulk-water temperature Coolant pressure in loop 2 
Fuel-rod-meat temperature 270 Steam-generator AT 2 
Surface temperature Reactor AT’ 2 
Flux measurement 80 Downcomer temperature 2 
In-core-boiling detectors 10 Coolant temperature inside steam generator 20 
Channel flow 25 Coolant temperature vertical section hot leg 2 
Fuel-element failure 20 Coolant temperature vertical section cold leg 2 
Internal structure & interpass AT vertical section hot leg 6 
Temperature 100 AT vertical section cold leg 6 
Pressure 5 Inlet-isolation-valve-body temperature 2 
External mechanical region Outlet-isolation-valve-body temperature 2 
Cooling-coil temperature 40 Steam-generator-shell temperature 15 
Cooling-coil flow rate 20 Coast-down flow measurement 2 
Internal-mechanisms temperature 40 Primary-coolant-pump rpm 4 
Motor-coil temperature 50 Main-coolant-valve piston Ap 2 
Latching-solenoid temperature 50 Thermal-trap temperature 6 
External-region-of-pressure-vessel temperature 50 Steam pressure upstream of main turbine 1 
Top-hat-shielding temperature 10 Steam temperature upstream of main turbine 1 
Shield-tank-water temperature (in cooling coils) 50 Ahead & astern turbine pressure 2 
Shield-tank-cooling-flow rate 5 Condenser pressure 1 
Power Plant Load-absorber torque 1 
Downcomer flow 2 Feedwater pressure 1 
Thermocouples in cooling jacket of feed-water- Turbine-generator-set-condenser pressure 2 
cooled components 7 Throttle-valve position 1 
Pressurizer-wall-temperature distribution 6 Turbine-throttle pressure 1 
Pressurizer steam quality 1 Power input to main pumps 4 
more of the following 6 sections: high- 
speed reducer, low-speed reducer, scram 
monitor, wide strip-chart recorders, 12- 
channel oscillograph, and temporary 
portable instruments. Data are all 
ready for feeding to a computer and 
can be stored efficiently so that data 
searches can be quick. 
Potential 
There are few limitations to what 
automatic data reduction can accom- 
plish. Performance is limited only by 
the customer’s imagination, his budget, 
and the know-how of the manufacturer 
of the data reducer. System simplic- 
ity will increase as confidence is gained 
in both reactor facilities and related 
instruments. The quantity of data re- 
quired will steadily decrease to a rea- 
sonable point. This epoch may be 
still 5-10 years off. 
System Requirements 
A typical power-reactor test loop is 
shown in Fig. 1. On it are indicated 
the points where sensing elements must 
monitor system variables. For such 
a loop there is always the question, 
46 
“What are the significant data to be 
recorded?” A final answer is seldom 
available until a detailed plant-test 
program is completed. Still, a 90% 
approximation of necessary recording 
instrumentation can be formed rather 
early in the plant design. If one de- 
signs a flexible system with enough 
room for spare input signals, it is safe 
to proceed with the equipment. 
Basic considerations. Several im- 
portant matters should be considered 
at the outset: (1) Flexibility in the sys- 
tem must allow for instrument rear- 
rangement and system expansion. (2) 
A standard input signal for the majority 
of the variables must be chosen early in 
the planning. Inputs of 0-20, 0-25, or 
0-50 millivolts are convenient, for 
there are amplifiers that can be con- 
nected to pressure and Ap transmitters 
and ionization chambers to produce 
linear millivolt outputs. (3) One must 
choose the form in which the data will 
appear on the final readout device; 
that is, in millivolts or directly in terms 
of the variables. (4) If a computer is 
available, readout on compatible mag- 
netic tape or punched cards is desirable. 
Strip-chart recorders. According 
to present information, the variables of 
Table 1 are important enough to be 
continuously recorded on wide strip- 
chart recorders. If these variables are 
desired for transient data, they can be 
fed simultaneously into the high-speed 
data reducer. 
Data reducers. All other required 
data, as listed in Table 2, are recorded 
in either the low-speed or high-speed 
reducers. In general the high-speed 
unit is totally engaged in recording re- 
actor information and a few variables 
in the heat exchangers. Little empha- 
sis is placed on determining the per- 
formance of a single component during 
plant operation. Such information is 
gathered prior to prototype startup in 
component-testing facilities. If single- 
component tests are necessary during 
plant operation, temporary portable 
instrumentation is provided. The re- 
actor is the one exception to this policy. 
It can be seen that much of the listed 
data is relevant to the performance of 
the steam generators. This has been 
found necessary for the following rea- 
sons: (1) Due to the reactor’s faster 
