5
PREVENTIVE MAINTENANCE
Periodic inspections are a necessary means to keep your level control in good working order. This control is a safety device
that protects the valuable equipment it serves. A systematic program of preventive maintenance should be implemented when
the control is placed into service. If the following instructions are observed, your control will provide reliable protection of your
equipment for many years.
What to do
1. Keep control clean.
Be sure the switch housing is always in place. This cover
is designed to keep dust and dirt from interfering with the
switch mechanism operation. In addition it protects
against damaging moisture and acts as a safety feature
by keeping bare wires and terminals from being exposed.
Should the housing cover become damaged or mis-
placed, obtain a replacement immediately.
2. Inspect switch mechanisms, terminals and connections
monthly.
Tuffy T3 level switches may sometimes be exposed to
excessive heat or moisture. Under such conditions insu-
lation on electrical wires may become brittle, eventually
breaking or peeling away. The resulting bare wires can
cause short circuits. Check wiring carefully and replace
at first sign of brittle insulation.
Vibration may sometimes cause terminal screws to
loosen. Check all terminal connections to ensure that
screws are tight. Check wiring carefully and repair or
replace if necessary.
Note: It is recommended that spare switches, housing
covers and o-rings be kept on hand at all times.
3. Inspect entire Tuffy T3 unit periodically.
A periodic cleaning of the float and counterweight assem-
bly will ensure continued free movement of the mecha-
nism.
What to avoid
1. NEVER leave the switch housing cover off of the control
longer than is necessary to make routine inspections.
2. NEVER place a jumper wire across terminals to “cut-out”
the control. If a jumper is necessary for test purposes,
ensure that it is removed before placing the control into
service.
3. NEVER attempt to make adjustments to or replace
switches without reading instructions carefully. When in
doubt, consult the factory or your local representative.
4. NEVER use in systems containing iron particles. The
magnet in the float assembly can attract the particles and
become jammed.
5. NEVER put insulation over the switch housing.
SPECIFICATIONS
Description
Specification
Switch ratings
Up to 10 A @ 240 V AC
Up to 6.0 A @ 24 V DC
Signal output
Single SPDT or single DPDT contacts
Switch types
Dry contact with silver or gold plated contacts
Hermetically sealed for corrosive environment
Approvals
ATEX II 1/2 G / IECEx Ex d IIC T6 Ga/Gb, flameproof enclosure
ATEX II 1 G / IECEx Ex ia IIC T6 Ga
NEMA 4X/7/9, Class 1, Div 1, Groups B, C & D
Cable entries
3
/
4
" NPT or M20 x 1,5
PHYSICAL SPECIFICATIONS
ELECTRICAL SPECIFICATIONS
Description
Specification
Measured variable
Liquid level
Physical range
Narrow differential: 13 mm (0.5")
Adjustable differential: up to 464 mm (18.26")
Interface Service Differential: 44 mm (1.72")
Interface: min S.G. difference between both liquids: 0,1
Ambient temperature
-40 °C to + 70 °C (-40 °F to +160 °F)
Process temperature
From -55 °C (-65 °F) up to 400 °C (750 °F) depending switch/housing selection
Process pressure
Standard models: up to 49,6 bar (720 psi)
High pressure models: up to 149 bar (2160 psi)
Wetted parts
316/316L (1.4401/1.4404) or Hastelloy C (2.4819)
Flange materials
Carbon steel
316/316L (1.4401/1.4404) or Carbon steel with 316/316L (1.4401/1.4404) cladding
Hastelloy C (2.4819) or Carbon steel with Hastelloy C (2.4819) cladding
Housing materials
Cast aluminium or cast iron
