Last update: 03/07/09
3
ELECTRIC LIFETIME OF THE CONTACT
The electric circuit, contained in the probe, consists of a reed switch that can function up to 1 million operations. Current
or voltage in excess, superior to the allowed limits, damage considerably the contacts reducing the electric lifetime (pit-
ting; sticking). To prevent these phenomena, it is necessary to evaluate with attention the transient ratings in which the
take off current might be 10/12 times the rating current.
The interruption of inductive loads can make the circuit reach different power readings (ddp) in the order of thousands of
volts. Therefore, take care in these situations of overload and excess voltage which are created during starting, circuit
closure and stoppage and circuit aperture. In order to prevent these distorsions it is necessary to foresee adeguate pro-
tections for the system. There are many circuits to choose from and one of the most common with effective remedy is
seen on fig.2
OPERATIONS
In order to prevent malfunctions, the flow switch must not be set near heat or magnetic sources. Do not store or handle
on full metal structures nor test the magnetic strength of the piston on magnetic material. It is advisable to properly
clean the system before operation in order to expell possible residual metal. The electric probe is stamped at the end of
the exit cable, indicating the setting in relation to the brass body and allows a correct assembly of the “reed” bulb. In
case of intervention or repair, follow this indication: wrong positioning could damage the probe.
PROBLEMS AND SOLUTIONS
PROBLEMS PROBABLE CAUSES SOLUTIONS
The Piston does not move - Insufficient flow
- Faulty assembly
- Piston jammed by scale and metal shavings
- Check leaks in the circuit
- Re-assemble, observing the flow direction
- Check, clean and or replace
Electric signal missing - Damaged “reed” electric contacts
- Electric connection incorrect or disconnected
- Un-phased probe or displaced
- Replace electric probe
- Provide eventual circuit protection
- Check and or repair
- Renew
REGULATIONS
:
see norm manual
The accessory hereby described bears the CE marking in accordance with the Norms and Directives applied on the
Declaration of Conformity.
For a correct utilization, follow the directions described in this manual and re-print them on the Use and maintenance
manual of the machine
Make sure that you are given the Original Conformity Declaration for the accessory chosen. The present manual is
valid for all Flowswitches named FL7
SPARES
Use only original PA spares, in order to benefit for a correct function and long reliability.
MAINTENANCE
Maintenance has to be carried out by Specialized Technicians.
Every 400 working hours (circa 10,000 cycles) check the magnetic pin (pos 3) and clean.
For a correct assembly, follow the phases indicated on the exploded view referred.
The Manufacturer is not to be considered responsable for damage as a result from incorrect fitting and mainte-
nance.
Technical data, descriptions and illustrations are indicative and liable to modification without notice.
