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MS4PMUHVT Multi-Stage Electronic Temperature Control with Relay Pack Product/Technical Bulletin
Deadband Mode
Deadband mode is used for applications requiring
cooling and heating. Where desirable, stages may
overlap or have space between them. See Figure 15.
Setpoint
is the desired temperature.
Setpoint 2
is width of the deadband, which is centered
on Setpoint.
In Direct Mode (cooling applications), the N.O. relay
contacts open, ending the On cycle when
Se (1/2 Setpoint 2) is reached on a
temperature drop.
In Reverse Mode (heating applications), the N.O. relay
contacts open, ending the On cycle when Setpoint -
(1/2 Setpoint 2) is reached on a temperature rise.
Differential
is the operational range of Stage 1.
Differential 2
is the operational range of Stage 2.
Setpoint 3
is the offset from the low end of the
deadband that activates Stage 3.
Differential 3
is the operational range of Stage 3.
Setpoint 4
is the offset from the high end of the
deadband that activates Stage 4.
Differential 4
is the operational range of Stage 4.
Interstage Time Delay
is the minimum amount of time
between two successive stages when multiple stages
are called for in rapid sequence.
Heating
Setpoint
Stage 1
Stage 2
Stage 4
Stage 3
Differential
Differential 2
Differential 4
Differential 3
Interstage
Time Delay
Time
Setpoint 4
(Offset from Stage 2)
Setpoint 3
(Offset from Stage 1)
Se (1/2 Setpoint 2)
Setpoint - (1/2 Setpoint 2)
Temperature
Cooling
On
On
On
On
Interstage
Time Delay
Setpoint 2 (Deadband)
(Centered on Setpoint)
Off
Off
Off
Off
Figure 15: Deadband Mode
