Fisher Scientific I903C, Руководство по эксплуатации

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The data transfer sequence is transmitted in the following format. X refers
to numerical temperature data.
(NUL) (-) XXX (SP) C (SP) (OVERTEMP) (SP) (LF) (CR) (EOT) (SP)
(UNDER TEMP)
The words "OVER TEMP" or "UNDER TEMP" are transmitted when
an alarm condition exists along with the temperature. If no alarm
condition exists, spaces will be sent. A total of 20 characters will be sent.
SP - Space LF - Line feed
CR - Carriage return EOT - End of text (4)
NUL - Null character (00)
Isotemp ULT freezers have remote alarm contacts and analog output. See
Figures 1-3 and 1-4 for the location of the remote alarm contacts. The
remote alarm connector is located in the parts bag provided with the
manual. It must be installed if connecting the freezer to an alarm system.
After installing the wiring from the
alarm system to the connector, install
the connector to the freezer
microboard and secure with the two
screws provided. The remote alarm
provides a NO (normally open)
output, a NC (normally closed)
output and COM (common). The
contacts will trip on a power outage,
high temperature alarm or low
temperature alarm. Figure 1-11
shows the remote contacts in alarm
state.
The analog output function allows the freezer to output signals
representing the temperature of the freezer cabinet. The factory default
setting is 4-20 mA. Refer to Table 1-2 for output specifications.
Isotemp ULT Chest 1-9 Fisher Scientific
Section 1
Installation and Start-up
Remote Alarm Contacts
and Analog Output
Figure 1-11. Remote Alarm Contacts
4-20 mA 0-1V 0-5V
Temperature -100 to +50°C -100 to +50°C -100 to +50°C
Table 1-2. Analog Output Specifications
IMPORTANT USER INFORMATION IMPORTANT USER INFORMATION
Caution! Stored product should be protected
by a redundant 24 hour/day monitoring
system with alarm capability. An interconnect
jack and thermocouple are installed
for centralized monitoring,should on-board
system fail.
RS-232 Communications
(continued)