Viconics H270 - Manual (Page 6)

6
TABLE 3: H263 HUMIDISTAT PROGRAMMING TOOL
CODE VALUES DEFAULT
VALUE DESCRIPTION
Db 0 to 40 % R.H. 25% R.H. Dead Band between humidification and dehumidification.
SL 30 to 100 % R.H. 85% R.H. Supply Limitation: High humidity limit in the supply duct (H270 only)
d2 0 to 199 % (of proportional
band) 100% Differential for output #2": Shift for output 2 relative to output 1
Pb 0 = 1.6 % R.H.
1 = 3.2 % R.H.
2 = 6.4 % R.H.
3 = 12.8 % R.H.
4 = 25.6 % R.H. 2= 6.4%
R.H. Proportional Band
o1 0 = Humidification
1 = Dehumidification "Output #1" Action for output no 1
o2 0 = Humidification
1 = Dehumidification "Output #2" Action for output no 2
cc 2 = Without integral
3 = With integral 3 "Control Code"
t1 0 = On/off
1 = 8 minutes
2 = 1 second "Time #1" Time period for output no 1
t2 0 = On/off
1 = 8 minutes
2 = 1 second "Time #2" Time period for output no. 2
rA 0 = °C
1 = °F 1 DO NOT
CHANGE "Range" Temperature Scale
Ca ± 13 % Calibration ( deviation mode: DO NOT MODIFY: USE AUTOCAL PROCEDURE; FOR
H100 TRANSMITTER, USE THE ZERO POTENTIOMETER ON THE TRANSMITTER.
hA 0 à 127 "Hardware assembly" Code related to thermostat model and entered at initial setup at
the factory.
it 1 to 99 = 1 TO 99 MINUTES 60 "Integral time" Error integration time.
Lt -40 à +40 °C (-40 à 105 °F) -20 °F "Lower temperature" minimum outside temperature for setpoint reset (model H270 only)
Ht -40 à +40 °C (-40 à 105 °F) 32 °F "Higher temperature" maximum outside temperature for setpoint reset (model H270
only)
rE 1 à 99 % R.H. 20 % R.H. "Reset” Minimum humidity value ( % HR ) (model H270 only)
Example: rE = 20%. Humidity setpoint will be reset from selected setpoint to 20%, from Ht
to Lt
AIR SUPPLY HIGH LIMIT HUMIDITY SENSOR
The H270 includes a high limit circuit. This allows the
use of a second humidity sensor to limit the humidity in
the supply air. Input signal goes to terminals #8 on the
humidistat. High limit setpoint is preprogrammed at
85%. It can be readjusted using the C263 service tool.
If you don’t use the high limit feature, connect a 4.7
Meg
Ω, ¼ watt resistor between terminals 8 and 10
(supplied with the humidistat.)
Remember: this high limit function is not a safety
device. For critical situations, provide installation with
normal protections required to ensure a safe operation.
TABLE 4 Example showing proportional high limit
override signal in supply duct.
SUPPLY HUMIDITY
100%
0%
50%
CO
NT
ROL OU
TPUT
LEV
EL
85%