Extech Instruments 48VTR User Manual page 18

Act Output control action. Set to "0" for cooling (direct) action or "1" for heating
(reverse/indirect) action.
unit Unit of measure selection. Program as follows:
0 degrees F
1 degrees C
2 Process analog inputs
dP Decimal Point selection.
00 no decimal point
01 0.1 resolution
02 0.01 resolution (for use with analog inputs only)
03 0.001 resolution (for use with analog inputs only)
Ct Cycle Time for relay output. Range: 0 to 100 seconds. This is the period of
time the controller waits between output changes. The longer the time, the
less responsive the controller will be to process changes. Set Ct for the
longest period of time possible without causing process oscillations; this will
help to prolong the life of the relay.
NOTE: Set 'Ct' to '0' seconds for the 4-20mA analog output option. Parameter
'Ct' is not used when ON/OFF control is used.
Hyst Hysteresis for ON/OFF control output. Users can create a deadband region
from 0.0 to 25.5% of SPAN. Hysteresis is used to eliminate control relay
chatter by creating a deadband where no relay action can occur. The
deadband region extends equally above and below the Setpoint. Note that the
SPAN is the region that extends from the Low Limit (LoLt) value to the High
limit (HiLt) value programmed in the 3
EroP Error Protection. The desired state to which the Control and Alarm relay
outputs default in the event of controller power loss.
Setting
0
1
2
3
Addr Not used; it must be set to '0'.
PVoF PV Offset. Permits the user to offset the PV indication from the actual PV. For
example, if the thermocouple used is producing readings 2
actual temperature across the range, the user can eliminate the 2
by programming a "-2" value for this parameter. Overall range of the setting is
-180 to +180. The default value is '0'.
rd
Menu Level.
Control output relay Alarm output relay
OFF OFF
OFF ON
ON OFF
ON ON
18 Model 48VTR - Version 5.0 – January 2006
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