Lauda RP 890 - Connecting External Loads

Proline Low-temperature Thermostats
24 Preparation YACE0072 / 21.08.07
6.4 Connecting external loads
Operation as circulating thermostat
− When used as circulation thermostat, care for
shortest hose connections with largest inner
diameter as possible. This gives the best flow.
− Push hose with 11-12 mm internal width onto
hose olive or connect metal hoses (Ì 6.3) to
pump conn
ectors.
− Pump connectors at si
de:
Inlet and outflow Ì see labeling housing.
− Pump connectors at back:
Inlet and outflow Ì see labeling housing.
− Set bypass valve to "external" (Ì 3).
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− If cross-sectional area of tube is too low Æ temperature gradient between bath
and external load due to low flow rate.
− Always ensure the largest possible passages in the external circuit.
− When tightening the union nuts on the pump nipple AF 19, use a wrench AF 14
to counter the tightening torque (see figure).
− If external control is to be used, provide a Pt100 probe in the external load (Ì
Section 7.7.2 and 7.7.4).
− With loads at a higher position and with stationary pump and ingress of air into
the thermostatic circuit, the external volume can drain away, even with closed
circuits Æ Risk of thermostat overflowing!
− Secure hoses against slippage with hose clips.
− Unused pump connectors must be closed off.