EBARA Press-o-Matic Instrucciones Para El Uso página 90

MASTER ST ATUS: when the device works as a MAS TE R it is s ensiti ve
to press ure c hanges in the plant and thus c apable of starting and
stopping the pump unit and modulating pump r pm i n acc ordance with
water demands from the plant.
SLAVE ST ATUS: when the device works as a SLA VE two capital S
charact ers appear on the display bottom line; in this c onditi on if the
pump is running the speed remains c onstant, whi le if the pump is
stopped its starting is i nhibited even when the taps are opened.
OPERAT ION: at the time of power-on the first device that gets the control over the other
becomes the MAS TER while the other f unctions as the SLA VE. When user services ar e opened
the MA STER device starts the pump and when the maxi mum rot ation speed is reac hed and the
system press ure is lower than the preset P min value, it tr ansf ers control to the second inverter,
which becomes the new MAS TE R, while the first i nverter bec omes the SLA VE and its rotation
speed remains fi xed. With the progressi ve closi ng of the us er ser vices the s econd device stops
the pump and c ontrol is again tr ansferred t o t he first inverter, which wi ll stop the electric pump
when the water demand is reduced to zero after complete c losing of eac h user. Aft er the
electric pump has been st opped MAS TE R status is again transferred to the other device to
ensure constant c hangeover of the pump that is started first. In t he event of a fault or error on
one of the two invert ers, the healthy device wi ll automatically ass ume MAS TE R s tat us and start
operating in stand-alone mode.
To acti vate the changeover function it is not necessary to s et any parameters in the menu
because Press•o•Mati c automatic ally detects the presenc e of a secondary device once the
electrical connection has been made.
T he Pmin a nd P max valu es set mus t be the same for both devices.
Installation and connection in twin
booster sets
INSTALL ATION: install eac h Press•o•Matic
unit on the pressure line of the corres ponding
electric pump. Connect the outlet union of
each inverter to the deli very manif old without
interposi ng a c heck valve. C onnect the
suction of the electric pumps to the common
intake manif old, i nterposing a c heck valve for
each pump t o prevent it from emptying when
stopped. Press•o•Matic is compatible with both
vertical and horizontal ins tallation.
CONNECTION: the two Press•o•Matic units
are connected by an unshielded 4x0.5 mm2
cable as shown i n the diagram beside. The
maxi mum cable length is 100 c m inc luding
stripped ends. Customers can order a
preassembled connection cable with terminals
and cable numbering - Ref. 362 400 414.
If no cable is c onnected the device will
functi on in stand-alone mode.
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