MS4PMUHVT Multi-Stage Electronic Temperature Control with Relay Pack Product/Technical Bulletin
11
Control Functions
Temperature Management Functions
SI
(Displays in Mode 4i only)
Setpoint
is the primary
temperature setting (°F or °C) programmed by the
user. For information on function in each mode, see
Modes of Operation
.
S2, S3, S4 Setpoint 2, Setpoint 3, Setpoint 4
depend
on the mode used. For information on function in each
mode, see
Modes of Operation
.
HI, H2, H3, H4 Differentials
are the difference (F° or
C°) between the value at which an output is switched
Off and the value at which an output is switched On
(relay contacts closing and opening, initiating or
ending an On cycle). For information on function in
each mode, see
Modes of Operation
.
HL, LL High and Low Setpoint Stops
are
temperature values (°F or °C) that define how high or
low the primary Setpoint may be adjusted. Setpoint
stops deter unauthorized or accidental overadjustment
of Setpoint.
Load Demand
Output Status
Cycle Delay
On
On
Off
Off
Time
Figure 17: Cycle Delay
Cc Cycle Delay, Cooling
establishes the minimum
time in minutes between two subsequent On cycles of
cooling (direct) stages. See Figure 17.
CH Cycle Delay, Heating
establishes the minimum
time in minutes between two subsequent On cycles of
heating (reverse) stages. See Figure 17.
iS Interstage Time Delay
is the minimum amount of
time between two successive stages when multiple
stages are called for in rapid sequence.
rt Soft Start
controls the rate at which the controlled
temperature is allowed to approach Setpoint on power
up, both initially and when the binary input is
configured as remote shutoff. The setting is
minutes/temperature units, such as minutes/F°. See
Figure 18.
Output Status
(up to four stages)
Sensed
Temperature
Setpoint
Temperature
Time (Minutes)
20
o
F
30
o
F
On
Off
20
2
4
6
8
10 12 14 16 18
Figure 18: Soft Start
Soft Start Example:
Temperature =
20°
Setpoint = 30°
Soft start = 2 minutes
Rate of Increase =
Soft start
x (
setpoint
– sensor reading)
Controlled temperature increases by 1° every
two minutes, until the setpoint temperature is
reached. To go from 20° to 30° takes 20 minutes.
So Temperature Sensor Offset
allows compensation
for temperature differences between actual and
displayed temperature, such as when using long
sensor leads. See Table 1 to determine the
temperature value to compensate for long sensor lead
extensions.
Un Temperature Units Used
allows selection of
Fahrenheit or Celsius temperature scale.
PU Display Refresh Rate
establishes the time delay
(seconds) between updates of the temperature
display.
Lc, Uc Heating Reset
and
Cooling Reset
are
automatic shifts of the
setpoint
, based on the
temperature at the Auxiliary Temperature Sensor
(ATS). See
Temperature Reset
for more information.
NC Non-compensated Band
establishes the
temperature range (F° or C°) over which reset does
not take place.
