user manual

14
Application, Operation, & Maintenance Manual DXM2 UNIT CONTROLS Heat Controller, Inc.
DXM2 Controls
setback is not connected and NSB is connected to Ground
“C”, then if OVR is momentarily connected to 24VAC
(minimum 1 second) then the OVR input is recognized
as a Night Setback Override signal and the DXM2Control
reverts from Night Setback and begins monitoring
thermostat inputs for heating and cooling calls for a 2 hour
override period. If NSB is connected to ground “C”, then if
OVR is continuously connected to 24VAC, then the OVR
input is recognized as a call for NLL Staged Heating and
the control enters NLL Staged Heating.
ESD – ESD is the input for Emergency Shutdown Mode.
When the ESD input is connected to Ground “C”, all inputs
are ignored and all outputs are turned off. There will be a
random start timer when coming back from ESD.
H – The H input function is determined by the setting of
DIP2.7, assuming the control is not controlling a internal
fl ow center or an accessory relay is not confi gured for
Whole House Dehumidifi cation or humidifi er operation.
If DIP2.7 = on then the H input is defi ned as Automatic
Dehumidifi cation Mode and is used as an “automatic”
counterpart to DIP1.5, meaning if H is connected to
24VAC then the selected fan outputs will operate using
dehumidifi cation speeds and airfl ow settings for cooling. If
H is not connected to 24VAC then the selected fan outputs
will operate using normal speeds and airfl ow settings for
cooling.
If DIP2.7 = off then the H input is defi ned as High Speed
Fan input and is used as an input to call for High Speed
Fan. If the control is in normal operating modes such as
Standby, Cooling or Heating AND the H input is connected
to 24VAC, then the selected fan outputs will operate
using high speed, or high speed airfl ows at all times (this
operation is a high speed fan version of the G input).
Other Outputs
Electric Heat – Outputs EH1 and EH2 turn on whenever
the DXM2 Control is in the following modes: Heating Stage
3, Emergency Heat, and Boilerless Operation.
Status LED – The Status LED is green. The Status LED
indicates the operating status of the DXM2 Control. See
Table 4: “LED and Alarm Relay Operation”.
Fault LED – The Fault LED is red. The Fault LED displays
the current operating status of the control, or fl ashes the
corresponding code for the last fault that has occurred
if the test mode is active. If there is no fault in memory,
then the Fault LED will fl ash Code 1. If the Fault type is
“Primary” (HP, LP, LT1, LT2, or CO) then the Fault type will
always be retained in memory (Primary faults will overwrite
Secondary faults). If the Fault type is “Secondary” (Over/
Table 5: System Inputs with the resulting demand.
Table 5 describes demand changes with differing system input (ESD,
NSB, OVR) and DIP input settings. Resulting Demand #1 is derived from
Table 4.
Table 6: "H" input with resulting demand modes.
Table 6 describes demand changes with “H” input and DIP 2.1-2.3, and
2.7 settings. Resulting Demand #2 is derived from Table 5.
Resulting Demand
#1 (From Table 4)
System Inputs
NSB Type
Resulting
Demand #2
(After ESD, NSB)
ESD NSB OVR
- X - - - ESD
Invalid - - - - Invalid
All (Excluding Invalid) - - - - All (Excluding Invalid)
All (Excluding Invalid) - - M - All (Excluding Invalid)
C1, C2 - - X - Invalid
OFF, F, H1, H2, or H3 - - X - NLL Staged Heating
EH - - X - EH
All (Excluding Invalid) - X - Mechanical Standby/OFF
All (Excluding Invalid) - X M Mechanical
All for 2 hours and
then revert to Stand-
by/OFF (Excluding
Invalid)
C1, C2 - X X Mechanical Invalid
OFF, F, H1, H2, or H3 - X X Mechanical NLL Staged Heating
EH - X X Mechanical EH
All (Excluding Invalid) - X -
Digital /
Comm
All (Excluding Invalid)
All (Excluding Invalid) - X M
Digital /
Comm
All (Excluding Invalid)
C1, C2 - X X
Digital /
Comm
Invalid
OFF, F, H1, H2. or H3 - X X
Digital /
Comm
NLL Staged Heating
EH - X X
Digital /
Comm
EH
“M” is momentary input
“X” is continuous input
Resulting Demand
#2 (From Table 5)
H
Auto Dehum / F2
DIP 2.7
Resulting Demand # 3 (After
DIP 2.1-2.3, 2.7 Logic)
Standby/OFF X Auto Dehum Mode Standby/OFF with Auto
Dehum enabled
Standby/OFF X High Fan Mode F2
F1 X Auto Dehum Mode F1 with Auto Dehum enabled
F1 X High Fan Mode F2
C1 X Auto Dehum Mode C1 with fan destage
C1 X High Fan Mode *Cooling with High Fan
C2 X Auto Dehum Mode C2 with fan destage
C2 X High Fan Mode *Cooling with High Fan
H1 X Auto Dehum Mode H1
H1 X High Fan Mode Heating with High Fan
H2 X - H2
H3 X - H3
EH X - EH
Invalid - - Invalid
* = signifi es that High Fan is locked on regardless of any Dehum demands