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17
2.
SET POINT (For positive temperature only)
- this is the user
changeable value for the Temperature Alarm relay.
3.
HYSTERESIS
(
value
)- this is the actual value of the hysteresis.
You can change this value from 0.0 to 19. 9°C. (See chapter
V
.
CONTROLLING THE RELAYS
.)
4.
RS 485 ID
– this is the unique ID/Address for the unit. If you are
connecting multiple model pH 550 or other Cole-Parmer models for
logging purposes then this ID/Address must be unique for each
connected unit. This ID/Address is the same address that must be
used by the PC program to communicate with this unit.
5.
PASSWORD SET
- this is your security code if the unit is locked
the value here will not be available. You need to input the correct
code in the PASSWORD CHECK page.
CAUTION
: The user is responsible in remembering their password
number otherwise you would no be able to calibrate or change the
settings.
V. CONTROLLING THE RELAYS
A. RELAY ISOLATION VOLTAGE
The maximum isolation voltage of the relay output contacts is 1500
VDC. The voltage differential between the relay output contacts and
the load should not exceed 1500 VDC.
B. RELAY OUTPUT LOAD
The current through the relay output contacts should not exceed 5
Amp at 115 VAC and 2.5 Amp at 230 VAC in order not to cause
permanent damage to the relay contacts. This rating is specified for
resistive
loads only.
C. RELAY ACTION, RELAY SETPOINT & HYSTERESIS VALUE