Danfoss EPU 2350 is a versatile and reliable controller designed for a wide range of heating and cooling applications. With its advanced features, it offers precise temperature control and efficient energy management. Here are some key capabilities of the EPU 2350:
-
Precise temperature control: The EPU 2350 maintains accurate temperature by continuously monitoring and adjusting the flow of heating or cooling media. Whether you're using it for underfloor heating, hot water systems, or refrigeration, you can trust it to deliver consistent comfort and efficiency.
-
Multiple sensor inputs: The controller can accommodate multiple temperature sensors, allowing you to monitor and control temperatures in different zones or areas simultaneously. This makes it ideal for complex heating and cooling systems where precise temperature management is crucial.
Danfoss EPU 2350 is a versatile and reliable controller designed for a wide range of heating and cooling applications. With its advanced features, it offers precise temperature control and efficient energy management. Here are some key capabilities of the EPU 2350:
-
Precise temperature control: The EPU 2350 maintains accurate temperature by continuously monitoring and adjusting the flow of heating or cooling media. Whether you're using it for underfloor heating, hot water systems, or refrigeration, you can trust it to deliver consistent comfort and efficiency.
-
Multiple sensor inputs: The controller can accommodate multiple temperature sensors, allowing you to monitor and control temperatures in different zones or areas simultaneously. This makes it ideal for complex heating and cooling systems where precise temperature management is crucial.
BC-HM VI.72.R1.02 Danfoss 1/94 1
Instruction
EPU 2350
Installer settings...............................
9-11
- f) Reduced temperature
- g) Integration time
- h) Proportional band
- i) Temperature difference
- j) Return temperature limiter
- k) Mini switches
Controller and sensor test ...............11
Manual valve control ........................11
Mounting .......................................12-14
- Wall mounting
- Board or panel mounting
- DIN-rail mounting
- Several controls in parallel
- Dismounting
- Time switch mounting
- Time switch dismounting
Contents
System examples.............................2-3
Wiring diagrams.................................. 4
Wiring ................................................... 5
Temperature sensor connections ..... 6
Frost protection .................................. 6
Time control ........................................ 6
External time switch ........................... 7
ESME override...................................10
External set point.............................. 11
Controller settings .........................8-11
User settings .........................................
8
- a) Time switch
- b) Temperature setting
- c) Function switch
- d) Indications
087R9344
087R9344
2 VI.72.R1.02 Danfoss 1/94 BC-HM
System example 1
System description
Instantaneous hot-water-service system
with heat exchanger control, 3-way valve
and secondary hot-water-service
circulation (pump P
b
).
Function
EPU 2350 controls motor valve to obtain
constant tap temperature at S1.
At time control tap temperature S1 can
be reduced and circulation pump P
b
is
stopped.
Wiring
See wiring diagram 1) for EPU 2350 -
230 V, page 4
Settings
Tap temperature can be set on button b)
BC-HM VI.72.R1.02 Danfoss 1/94 3
System example 2
System description
Hot-water-service system with heat
exchanger and storage tank. Charge
temperature control is controlled by a
3-way valve mounted in the primary heat
exchanger circuit. Pump P
c
is used for
tank charging and pump P
b
for tap water
circuit circulation.
Function
Heat exchanger is connected direct to
district heating system and primary
control valve controls charging circuit
temperature (S1). Hot-water cylinder has
one (S2) or two (S2 and S2*) sensors.
Pump (Pc) in charge circuit is cut-in
when cylinder temperature S2 (top
sensor) is lower than cut-in temperature
and stopped when reaching cut-out
temperature S2* (bottom sensor).
At time control tap temperature S1 can
be lowered and circulation pump P
b
is
stopped.
Wiring
See wiring diagram 2) for EPU 2350 -
230 V, page 4
Settings
- Charge temperature S1 is set on
temperature button b).
- Cut-in temperature S2 = S1 − (setting
DIL 4) − ∆ T potentiometer j.)
Cut-out temperature S2* = S1 −
(setting DIL 4)
Note:
At hot-water service flow through heat
exchanger, mini-switch 5 must be set in
position ON (control) to maintain charge
temperature in circulation pipe during
pump P2 standby.
On hot-water-service flow through
storage tank (system example 2) mini-
switch 5 must be set in position OFF.
Charge temperature S1 is then kept at
+6°C (frost protection) at pump P
c
standby .
4 VI.72.R1.02 Danfoss 1/94 BC-HM
Wiring diagrams
Wiring diagram 1) for EPU 2350 (230 V)
Wiring diagram 2) for EPU 2350 (230 V)
BC-HM VI.72.R1.02 Danfoss 1/94 5
Wiring
Terminal strips
Terminal strips with screw fastening wire
the controller.
Each terminal can wire up to 3 x 1.5 mm
2
or the like. The terminals are encoded,
so units with supply voltage cannot be
wired in the safety voltage part.
Wiring EPU 2350 - 230 V a.c.
Connections with supply voltage - (terminals 13 - 24)
Terminal Load
Zero (N) - 230 V a.c. 13
Phase (L) - 230 V a.c. 14
16 (close) 8 (2) A 250 V a.c.
Reversible gear motor 230 V a.c. - AMB, AMV
17 (open) 8 (2) A 250 V a.c.
Relay outlet (R1) 230 V a.c.- NC 21 - 22 8 (2) A 250 V a.c.
Relay outlet (R2) 230 V a.c. - NC 23 - 24 8 (2) A 250 V a.c.
6 VI.72.R1.02 Danfoss 1/94 BC-HM
Temperature sensor connection, etc. - safety voltage (terminals 1 - 12)
Sensor and remote unit mounting is described in instructions, which are delivered
together with the products.
Type Terminal
S1 Temperature sensor - flow ESMU 10 - 11
S2 Cylinder temperature sensor
ESMU 7 - 9
- top sensor in hot water cylinder
S2* Cylinder temperature sensor
ESMU 8 - 9
- bottom sensor in hot water cylinder
S4 Temperature sensor - return ESMA/C/U 4 - 6
S3 Temperature sensor - frost protection ESMA/C/T 11 - 12
S5 Set point remote setting ESME 4 - 5
External time switch signal connection ECA 9010 3 - 4
BUS for communication 1 - 2
Wire cross section: min 0.4 mm
2
Total length of all sensor and BUS wires.
Max. 150 meter.
Note!
The measure result might deviate due to
wire resistance. A resistance of 4 Ohm
corresponds to a deviation of about 1 K.
Frost protection
EPU 2350 has built-in frost protection,
which prevents S1, S2 or S4 sensor
temperatures to fall below +6 °C, i.e. R1
and R2 are not activated (circulation
pump cut-in).
On connecting a separate S3 frost
protection sensor the whole system can
be frost protected at +2 °C . R1 and R2
are not activated (circulation pump cut-
in) when sensor temperature S3 falls
below +2 °C.
If circulation pumps must operate at
outdoor temperatures below +2°C
outdoor sensor ESMT must be mounted
on S3.
When several controls are coupled
outdoor temperature signal (frost
protection sensor S3) is transferred via
BUS.
Time control
EPU 2350 can be time controlled via a
built-in time switch mounted in the
controller or via an external time switch
Time switch type Reduced temp R1 R2
1-zone time switch follows zone 1 follows zone 1 always ON
2-zone time switch follows zone 1 follows zone 1 follows zone 2*)
ECA 9020 follows zone 3 follows zone 3 follws zone 4*)
*) applies to system example 1 only
or manual switch. Relay outlets R1 and
R2 status depends on time switch
setting.
BC-HM VI.72.R1.02 Danfoss 1/94 7
External time switch
ECA 9010 is connected to time switch
inlet terminals 2, 3 and 4 and used for
external time control. Time control only
applies to relay outlet R1 and can be
received by the control only when
function switch is set in position
.
Time switch or manual switch can be
connected to ECA 9010 inlet terminals 1,
2 or 3. Following time control functions
are available.
ECA 9010
Function
terminals
Normal temperature 2 and 3
Reduced temperature 1 and 3
If the contact set is gold-plated the
external time switch is connected directly
to the control terminals 3 and 4.
ESME override
Remote control module ESME
connected to terminals 4 and 5 is used
for external override. Override signal
only applies to relay outlet R1 and can
be received by the control only when
function switch is set in position
.
Temporary reduced temperature
override
Use external override module (ESME
connected to terminals 4 and 5 or
external time switch connected to
terminals 3 and 4) for 2 hours temporary
external reduced temperature override.
Override is cut-in on setting function
switch for ESME or for time switch in
for 5 to 30 sec. and then back to .
Override is cancelled on setting function
switch in for 5 to 30 sec. and then
back again
.
External set point
Normal temperature can be set
externally on remote setting module
ESME potentiometer. ESME is
connected to terminals 4 and 5 and
overrides normal temperature setting in
control P 8.0.
Note!
Override or external set point
connected to terminals 4 and 5 cannot
be applied at the same time as external
time switch on terminals 3 and 4.
8 VI.72.R1.02 Danfoss 1/94 BC-HM
Automatic changeover between
normal and reduced temperature
according to time switch settings.
Constant normal temperature. Time
switch is overridden.
Manual control. Controller function
off. Valve motor receives no control
signals, use button b) for manual
valve control.
d) Indications
ON - alight, when controller has been
connected and functions properly
- off, if controller is defect or if S1
sensor is interrupted, short-
circuted or missing
- flashes, when frost protection is
active. Frost protection is active
when:
- S1, S2, or S4 are lower
than +6 °C
- S3 is lower than +2 °C.
- flashes together with
when
function switch is set in position
. Number of interruptions
show number of connected
sensors.
- alight at reduced temperature
control
- flashes together with ON when
function switch is in position
Number of interruptions show
number of connected sensors.
▲ alight as long as gear motor
receives signal to open the valve
(to increase temperature).
Shortest signal is 0.5 sec.
▼ alight as long as gear motor
receives signal to close the valve
(to reduce temperature). Shortest
signal is 0.5 sec.
Controller settings
User settings
a) Programmable time switch
b) Temperature setting
c) Funktion switch
d) Indications
e) User guide
a) Time switch
Analog time switch is set in the required
normal and reduced temperature periods
in pushing riders for reduced temperature
settings towards the center of the time
switch.
Set actual time and week day vis-a-vis
the mark in turning the dial in arrow
direction
Digital time switch ECA 9016, see
enclosed user guide.
b) Temperature setting
Use the temperature knop for setting
required storage or flow temperature
(reference temperature for S1). Setting
range 30 - 70 °C.
c) Function switch
Valve closes and circulation pump
stops, frost protection at 6 °C.
Constant reduced temperature.
Time switch override
BC-HM VI.72.R1.02 Danfoss 1/94 9
Installer settings
f) Reduced temperature -
g) Integration time - T
n
h) Proportional band - X
p
i) Temperature difference at ON/OFF-
cylinder charge control - ∆T
j) Return temperature limiter -
k) Miniswitches
f) Reduced temperature -
Setting range 1 - 40 K and OFF.
Controls with time switch can reduce
normal temperature according to
potentiometer f) settings of period and
degrees
If potentiometer is set in pos. OFF
temperature will be reduced to frost
protection limit (+6°C) during the
required period.
g) Integration time - T
n
Setting range 0 - 10 minutes and OFF.
Integration time states the time that runs
until I-function has changed the output
signal like P-function. A short time
results in a quick control but large
overshooting (risk of unstability)
If the potentiometer is set in pos. OFF,
the integration function is off and the
proportional band X
p
will equal the
neutral zone. The function is similar to a
3-position thermostat.
h) Proportional band - X
p
Setting range 1 - 40 °K.
Proportional band states temperature
range, where motor control impuls period
is proportional to temperature deviation.
Beyond this range, the control impulse is
constantly ON. A small proportional band
is at risk of unstable control.
i) Temperature difference - DT
Setting range is 1 - 30 °K
This function is in operation only in
storage charge systems with 1 or 2 S2-
storage sensors.
1 storage sensor:
S2 sensor temperature difference
between cut-in and cut-out temperature
2 storage sensors:
Temperature difference between cut-in
temperature (top sensor S2) and cut-out
temperature (bottom sensor S2*)
j) Return temperature limit -
Setting range 30 - 70 °C.
Return temperature is limited according
to temperature setting, potentiometer j).
Choose minimum or maximum
temperature limit (switch 1) and
amplification 4 or 8 (switch 2). S1
reference is reduced when return
temperature limit is operating.
10 VI.72.R1.02 Danfoss 1/94 BC-HM
k) Miniswitches
EPU 2350 has have eight miniswitches
(DIL-switches). The miniswitches are
used for special settings and functions.
Do not change these factory settings!
Switch 1 - Return limit function
Choose maximum or minimum return
temperature limit of potentiometer
temperature j). At maximum or minimum
limit return temperature is kept below or
above temperature setting, respectively.
S1 reference is reduced.
Switch 4 - operation difference
between S1 and S2
(This function is used only in charge
circuit systems)
Choose operation difference between
charge temperature (temperature setting
- S1) and S2 (S2*) sensor cut-out
temperature.
Switch 4 Difference S1 - S2
ON 10 K
OFF 5 K
Switch 5 - Charge temperature S1 at
standby
(This function is used only in charge
circuit systems)
Choose charge temperature at standby,
i.e. charge temperature is maintained
(valve is operating) or frost protection
+6°C (valve is closed)
Switch 5 function
ON valve operates
OFF valve is closed
Switch 6 - Valve/motor constant
Choose approx. valve motor operation
period from closed to open valve
Switch 1 Funktion
ON max. limit
OFF min. limit
Switch 2 - Return limit amplification
Choose return limit amplification (i.e. S1
reference temperature reduction at each
return temperature deviation degree.
Switch 2 amplification
ON 8 times
OFF 4 times
Switch 3 neutral zone
ON 3 K
OFF 1 K
Switch 3 - neutral zone
Choose neutral zone for PI-control
circuit. Valve motor receives no signal
when temperature is within the neutral
zone.
Switch 6 function
ON 20 sec (quick)
OFF 120 sec (slow)
BC-HM VI.72.R1.02 Danfoss 1/94 11
Switches 7 and 8 - Addressing
When controller is coupled with other
EPU or ECL controls via BUS, the
controller must be given an address. See
paragraph "Master/slave units".
Following addresses are available:
Switch
Address
78
OFF ON 0
ON ON 1
ON OFF 2
OFF OFF 15
Controller self-test and sensor test
EPU 2350 can operate both self-test and
sensor test. Set function switch in
position
. After approx. 5 sec. both
ON and
will flash and show test
result. The result will be repeated every
3rd second.
Test result can show:
1, 2, 3, 4, or 5 interruptions
Number of interruptions corresponds to
number of connected sensors. If the
number of interruptions does no
correspond, one or several sensors
might be defect or are not connected.
No light
Controller is defect or S1 sensor is not
connected.
Constant light
The controller is defect.
Manual valve control
When testing or adjusting gear motor
limit switches valve can be manually
controlled in setting function switch in
position
and turning temperature
button.
Open valve
Turn temperature button b) all the way
to the right (clockwise)
Close valve
Turn temperatue button b) all the way to
the left (anti-clockwise).
If the motor does not rotate in correct
direction wires must be interchanged, i.e.
terminals 16 and 17.
12 VI.72.R1.02 Danfoss 1/94 BC-HM
Monting
On wall
Use standard base plate or special base
plate with wall case for mounting EPU
controller.
The plate is fixed on a flat surface with
two Ø 4 mm screws (standard base plate)
or three Ø 4 mm screws (special base
plate). Be aware of the "UP"-arrow.
Then wire EPU controller as described in
paragraph "Wiring".
EPU is mounted in base plate (when
using speical base plate, note that the
controller is first of all to be fit into the
wall case) and screw up the center screw
behind the cover plate.
In panel
EPU can be built into a panel. The
opening is to measure 92 x 138 mm and
the plate is to be max. 3 mm thich.
Fix four retainer springs on the controller,
push it gently into the opening and the
springs will secure the controller in the
opening. The retainer springs are
delivered as accessories togeter with 2
terminals strips.
Wire EPU to the two terminal strips and
then mount them in the controller. The
terminals strips are encoded to prevent
exhange by mistake.
On DIN-rail
EPU can be mounted on a 35 mm DIN-
rail. Fix a spring - delivered as accessory
- on the base plate bottom and then
mount the base plate on the DIN-rail.
BC-HM VI.72.R1.02 Danfoss 1/94 13
In panel
On wall or DIN-rail
Several controllers in parallel
Dismounting
Controllers in panels are dismounted in
pressing retainer springs together and
pushing controller out.
When retainer springs are not accessible
use a screw driver to tip out the
controller.
14 VI.72.R1.02 Danfoss 1/94 BC-HM
Time switch mounting
Remove glass cover, inside cover and
time switch cover and then mount time
switch.
Open the glass cover all the way to the
left - the pintles will then slide out. Tip
out inside cover and unscrew time switch
cover.
Time switch is placed in the center of the
opening with plugs downwards.
Time switch dismounting
Remove screws and gently tip out time
switch.
BC-HM VI.72.R1.02 Danfoss 1/94 15
16 VI.72.R1.02 Danfoss 1/94 BC-HM
-
1
-
2
-
3
-
4
-
5
-
6
-
7
-
8
-
9
-
10
-
11
-
12
-
13
-
14
-
15
-
16
Danfoss EPU 2350 is a versatile and reliable controller designed for a wide range of heating and cooling applications. With its advanced features, it offers precise temperature control and efficient energy management. Here are some key capabilities of the EPU 2350:
-
Precise temperature control: The EPU 2350 maintains accurate temperature by continuously monitoring and adjusting the flow of heating or cooling media. Whether you're using it for underfloor heating, hot water systems, or refrigeration, you can trust it to deliver consistent comfort and efficiency.
-
Multiple sensor inputs: The controller can accommodate multiple temperature sensors, allowing you to monitor and control temperatures in different zones or areas simultaneously. This makes it ideal for complex heating and cooling systems where precise temperature management is crucial.
Ask a question and I''ll find the answer in the document
Finding information in a document is now easier with AI
Related papers
-
Danfoss EPU 2350/2354 Operating instructions
-
-
-
-
-
-
Danfoss ESMA Installation guide
-
-
-