Thermo Electron 3751, Инструкция по установке и обслуживанию

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2
GENERAL INFORMATION
The incubator is commonly referred to as the
standard Model 818. These instructions
encompass the models listed below with their
specific electrical characteristics.
NOTE
CATALOG NO. 3166748 CAN BE CONVERTED FOR
OPERATION ON 200 V OR 240 V BY CHANGING
INPUT CONNECTIONS TO THE
AUTOTRANSFORMERS (SEE WIRING DIAGRAM ON
PAGE 19).
The 818 Low Temperature Illuminated Incubator
has been designed to provide the ultimate in
temperature control. The user is assured of
dependable and precise performance through the
use of microprocessor technology in the
temperature control circuitry. The 818 is operable
in the range of -10° to +50°C without illumination
and +10° to +50°C with illumination. These
temperature ranges will meet a wide variety of
applications, such as BOD determination, general
incubation and the preservation of critical materials.
PERFORMANCE DATA
Heat-Up Time: From -10°C to 50°C; 120 minutes
(Compressor "ON");
Cool-Down Time: From 50° to -10°C; 100 minutes.
NOTE
THE ABOVE PERFORMANCE FIGURES ARE BASED
UPON THE FOLLOWING OPERATING CONDITIONS:
LINE VOLTAGE ............... 110.5 TO 112.5
AMBIENT TEMPERATURE ... 22.5° TO 24°C
Theory of Operation
The refrigeration system, defrost heater, and air
circulating fan are used in conjunction with a
microprocessor controlled proportioning circuit to
achieve sensitive temperature control. A RTD
(Resistance Temperature Detector) located in the
airstream senses any temperature deviation from
the control point, and heat is provided proportionally
to maintain the desired temperature. Regardless
of what temperature is being maintained, the
compressor operates continuously. This constant
operation alleviates component failures associated
with cycle type operation.
The circulating fan provides even air distribution
throughout the chamber and assures temperature
uniformity.
The program mode of the 818 illuminated incubator
allows the user to program into memory 2 sets of
values for time, setpoint temperature, and light
condition per day for a full week. The following is
an example of a schedule and a pictorial describing
the events during that week. A blank schedule
sheet is provided at the rear of the manual for the
user to copy and then document a schedule. It is
strongly recommended to do this before any
programming is performed.
Catalog Volts Hz Amps
3751
3752
115
230
60
60 7.5 A
3.75 A
e r u t a r e p m e T
t n i o P t e S
) C ° (
) C ° ± ( y t i m r o f i n U
e r u t a r e p m e T
y t i v i t i s n e S
t u o h t i W
n o i t a n i m u ll lI
h t i W
n o i t a n i m u ll I
0 . 0 1 - 0 . 2 ± A / N
C 2 . 0 ±
0 . 0 1 + A / N 8 . 1 ±
0 . 0 2 + 6 . 0 ± 5 . 1 ±
0 . 7 3 + A / N A / N
0 . 0 5 + A / N 7 . 0 ±