Auxiliary Accessories Connection (Fig. 17); 3-Way Valve; Frequency Limitation; Stop Unit Or Defrosting Signals - Galletti Inverter technology MCI Manual De Instalación

8 - AUXILIARY ACCESSORIES CONNECTION (FIG. 17)

8.1 - 3-way valve

The MCI units drive a 3-way valve to manage a sanitary water
storage tank. The operating logic provides that, in case of a
request for sanitary water by an accumulation tank, the
system controls a 3-way valve to direct the hot water only to
the tank and to operate at the maximum capacity to provide
water at 60 °C (compatible with the operating envelope).
For operation, connect the 3-way valve between PINS 18, N
and 10 of the terminal strip (see Fig. 17). PINS 18 (Line) and N
(Neutral) power the valve (1ph ~ 230V, 2A max), and a
command signal (1ph ~ 230V, 2A max) is available on PIN 10.
If using a valve with spring return, only connect PINS 10 and
N.
The sanitary water request signal must be a Dry Contact type
(contact quality greater than 25mA @ 12V) that closes the
circuit between PINS 15 and 13 of the terminal strip (see Fig.
17).
ATTENTION: The sanitary water request has higher priority
than the programmed operating mode in both heating and
cooling mode.

8.2 - Frequency limitation

To force the unit to operate at a lower maximum frequency
(to reduce noise) in the absence of a User Comfort Interface,
provide a Dry Contact (contact quality greater than 25mA @
12V) between PINS 13 and 14 of the terminal strip (see Fig.
17). With the contact closed, the unit will operate with a
maximum frequency lower than the standard one, otherwise
it will operate in standard mode.
For correct operation, it is necessary to configure the unit
using parameters 5 and 6 from the User Interface menu.
The maximum noise reduction is about 3dB at 75% of the
maximum operating frequency of the compressor.

8.3 - Stop unit or defrosting signals

There are several signals available on the terminal strip to
indicate particular conditions or the stop of the external unit.
The available signals are:
• Defrosting: When operating in Heating mode,
depending on the external environmental conditions,
the unit could perform defrosting cycles to clean the
external battery of any ice formations. Under these
conditions, it is not possible to guarantee the requested
temperature output water temperature, which could
reduce general comfort.
(PINS: 4-N, NUI CODE: 106 or 108)
• Alarm: Indicates an alarm condition that stops the
compressor. (PINS: 5-N, NUI CODE: 147 or 108)
• Ambient Temperature Reached: If suitably programmed
using the User Comfort Interface (NUI), and operating
with this interface, a signal is provided that indicates
22
RG66012647

8.4 - External temperature probe

If the positioning of the external unit could induce a non-
representative reading of the external temperature by the
probe positioned on the machine, an additional temperature
probe can be provided (NTC 2 wire, 3kΩ @ 25°C, code:
33AW-RAS01) remote. Connect the terminals of the probe
between PINS 23 and 24 of the terminal strip (see Fig. 17).

8.5 - Dehumidifier or Humidifier

A Dehumidifier or a Humidifier can be driven using humidity
sensor into 33AW-CS1B interface.
Connect electrically a Dehumidifier or a Humidifier to N, 11
terminals to a relay that drives Dehumidifier (NO contact) or a
Humidifier (NC contact) Configure NUI code 108 (2 for
dehumidifier /Humid.)
Configure ambient humidity limit (NUI CODE 107) where
Dehumidifier or a Humidifier is activated (eg. with code 107 =
65, Dehumidifier is activated with ambient humidity >UR65%
5% hysteresis).

8.6 - Additional water pump (ADD WP)

It is possible to connect an additional water pump through
the pins 12 and N. It is managed in the following way:
If OAT > temperature set in NUI code 148.
The additional water pump activation depending by the NUI
code 156.
1.
2.
If OAT < temperature set in NUI code 148.
The additional water pump activation depending by the
NUI code 157 (0. always of, 1. on/of depending by EHS, 2.
always on).
All copying, even partial, of this manual is strictly forbidden
that the pre-set temperature has been reached. This
signal can be used as the contact window normally
implemented in the fan-coils.
(PINS: 5-N, NUI CODE:147)
Several outputs are used for more than one condition. It
is possible to configure these outputs through the User
Comfort Interface installation menu (refer to the
manual).
Refer to the tables on the next two pages for the correct
pin-outs and use of the signals.
ON/ OFF depending on the outdoor unit water pump
logic, in case of SHW activation ADD WP is ON;
ON/ OFF depending on the outdoor unit water pump
logic, in case of SHW activation ADD WP is OFF;