On/Off Operation; Modulating Operation - Carel compactSteam Mode D'emploi

3.10 On/Off Operation

The diagrams shown in the figures on the side indicate the
connections to be performed on the terminal block in the
following situations:
Fig 3.s operation controlled by a simple voltage-free remote
enabling contact, indicated as CR;
Fig 3.t operation controlled by an external mechanical
humidistat, indicated as H;
Fig 3.u a combination of the above.
Remote enabling contact (fig.3s)
Remove the jumper between terminals AB-AB and connect the
voltage-free remote contact (CR) in series to terminals AB-AB;
terminals IN-GND must be jumpered. When contact AB-AB is
closed, the humidifier is enabled for operation; if the contact is
open, steam production stops immediately.
Fig. 3.s
External humidistat without enabling (fig. 3.t)
Connect the external humidistat between terminals IN-GND and
leave the jumper in position between terminals AB-AB. DO NOT
apply any voltage to AB-AB. If the IN-GND contact is closed, steam
production starts, while if it is open steam production stops after
5 s.
N2
G ND
N1
AB
AB
G ND
IN
Fig. 3.t
External humidistat with enabling (fig. 3.u)
Connect the external humidistat between terminals IN-GND.
Remove the jumper between terminals AB-AB and connect any
limit devices, air flow switches or remote contacts (CR) in series
to terminals AB-AB. Steam production only starts when both
contacts, AB-AB and IN-GND, are closed. If contact AB-AB is open
steam production stops immediately, while if IN-GND is open
production stops after 5 s.
N2
G ND
N1
AB
AB
G ND
IN
Fig. 3.u
"compactsteam" +03U0092EF - rel. 1.0 - 2020.08.31
H
C R (1)
H
Interlock between compactSteam for ducts and the
system fan controller
In duct applications, compactSteam starts steam production
only if there is an external call for humidity (humidistat closed)
and the system fan is on. The system fan communicates with
compactSteam via the remote input AB-AB. The following
sequence of events must be true for compactSteam to produce
steam:
• External humidistat close (= steam demand);
• FAN-EXT contact closed by compactSteam, to start the system
fan;
• Input AB-AB closed, indicating that the fan has started (=
enable steam production).
compactSteam can be connected to an air flow switch (that is, a
device that senses the flow of air generated by the fan in the duct).
This flow sensor should be connected to the remote enabling
input (terminals AB-AB) in series with a limit humidistat (normally
closed). When the flow sensor is connected to compactSteam,
steam production is only enabled if air flow is measured inside
the duct.
Fan symbol
• Off: no call (IN-GND = open), regardless of whether or not
production is enabled (AB-AB = open or closed);
• Flashing: call present (IN-GND = closed), awaiting production
to be enabled (AB-AB = open);
• On steady: call present (IN-GND = closed) and production
enabled (AB-AB = closed).
Note:
• When enabled (AB-AB = closed), the symbol goes off 30 s after
the production call is no longer present (IN-GND = open);
• When the production call is present (IN-GND = closed), the
symbol goes off 60 s after production is disabled (AB-AB =
open).

3.11 Modulating operation

Connect the external 0 to 10 V modulating control device
between terminals IN-GND as shown in Fig. 3.v. Then connect
any safety switches (limit device, air flow switch, remote on/off )
in series to terminals AB-AB.
If no safety switches are used, install a jumper between AB-AB. DO
NOT apply any voltage to AB-AB.
Steam production is modulated from 20% to 100% of the
maximum production, proportionally to the signal provided by
the external controller.
22
Fig. 3.v