Series 301 Top Mount Float Type Level Control

Top Mount Float Type Level Control Single Stage for Alarms, Depth to 12 ft.

Single Stage for Alarms, Depth to 12 ft.

The reliable 301 Series has proven to be a rugged economical choice for top mounting on tanks where side mounting is not practical, or for use in sumps. These units feature a fixed deadband for high or low alarm or shutdown. This control can be mounted on top of any closed or open tank or sump by use of the 3/4" NPT connection. Flanges are also available in various sizes, pressure rating and material to meet any installation. Several size floats are available to accommodate liquids to a specific gravity of 0.5 and depths to 12 feet.

Electrical switch actions, SPST, SPDT, DPDT, or DPST, can be ordered to satisfy most applications. Two-stage operation available, consult factory. Hermetically sealed snap action or mercury contacts provide for high or low current or voltage requirements. Enclosures include general purpose NEMA 1, weatherproof NEMA 4, explosion-proof NEMA 7, 9. The explosion-proof, vapor proof version combines weatherproof, vapor proof, and explosion-proof NEMA 4, 7, 9 construction in one enclosure. The 301 Series can be used on pressurized vessels.

Product Applications

  • Oil Refineries
  • Chemical Plants
  • Power Generating Stations
  • Pumping Stations
  • Sanitary/Waste Water Facilities
  • Sumps
  • Open or Closed Tanks and Vessels
More Information
Model Chart
EXAMPLE 301 G 4810 AS 15 1.0 2 STW 301-G-4810-AS-15-1.0-2-STW Top mount Float Type Level Control, NEMA 1 enclosure, single stage mercury switch, 3-1/2" x 6" 304SS float, 316SS stops, 304SS extension, 1.0 specific gravity, 4" 125# cast iron flange, with SS tag.
SERIES 301               Top Mount Float Type Level Control
ENCLOSURE   G             General Purpose, NEMA 1
  WT             Weather tight, NEMA 1, 2, 3, 4, 4X
  E             Explosion-proof, NEMA 7, 9, Class I Groups B, C, D, Class II Groups E, F, G, Div. I & II; CSA approved Groups C, D, E, F, G only
  EV             Explosion-proof/Vapor-proof, NEMA 7, 9, Class I Groups B, C, D, Class II Groups E, F, G, Div. I & II; CSA approved Groups C, D, E, F, G only
CIRCUITS     48XX           Single Stage Mercury Switch, see chart A
    78XX           Single Stage, Snap Switch, see chart A
    78XXHM           Hermetically Sealed Snap Switch, see chart B
    98XX           Single Stage, High Capacity DC Snap Switch, use heat fins (HF) if process temperature exceeds 350°F (177°C), do not exceed 450°F (232°C), see chart B
FLOAT/
STOP/
GUIDE ROD
      00         No Float, No Guide Rod
      AS         3-1/2" x 6" 304SS Float, 316SS Stops, 304SS Extension
      BS         4-1/2" Copper Float, 316SS Stops, 304SS Extension
      CS         4-1/2" 304SS Float, 316SS Stops, 304SS Extension
      DS         7" 304SS Float, 316SS Stops, 304SS Extension
      ES         7" Copper Float, 316SS Stops, 304SS Extension
      A0         3-1/2" x 6" 304SS Float, 316SS Stops, No Extension
      B0         4-1/2" Copper Float, 316SS Stops, No Extension
      C0         4-1/2" 304SS Float, 316SS Stops, No Extension
      D0         7" 304SS Float, 316SS Stops, No Extension
      E0         7" Copper Float, 316SS Stops, No Extension
OPERATING
POINT
        XX       ≥12 or ≤96. See Dimensional Drawing.
SPECIFIC
GRAVITY
          1.0     1.0 Specific Gravity
          .9     0.9 Specific Gravity
          .82     0.82 Specific Gravity
          .75     0.75 Specific Gravity
          .62     0.62 Specific Gravity
          .50     0.50 Specific Gravity
FLANGE             0   No Flange
            2   4" 125# Cast Iron
            3   5" 125# Cast Iron
            4   6" 125# Cast Iron
            5   8" 125# Cast Iron
            7   4" 150# RF Carbon Steel
            8   5" 150# RF Carbon Steel
            9   6" 150# RF Carbon Steel
            10   8" 150# RF Carbon Steel
            12   4" 300# RF Carbon Steel
            13   5" 300# RF Carbon Steel
            14   6" 300# RF Carbon Steel
            15   8" 300# RF Carbon Steel
            17   4" 250# RF Cast Iron
            18   5" 250# RF Cast Iron
            19   6" 250# RF Cast Iron
            20   8" 250# RF Cast Iron
            7S   4" 150# RF 316SS
            8S   5" 150# RF 316SS
            9S   6" 150# RF 316SS
            10S   8" 150# RF 316SS
            12S   4" 300# RF 316SS
            13S   5" 300# RF 316SS
            14S   6" 300# RF 316SS
            15S   8" 300# RF 316SS
OPTIONS               HF Heat Fins
              R Manual Reset - Single Stage
              R1 Manual Reset - Lower Stage 2-Stage Control
              STW SS Tag Wired
              01 Breather Only (E-Housing only)
              02 Drain Only (E-Housing only)
              12 Breather and Drain (E-Housing only)
              14210.40 Spec. 14210 for Sch 40
              14210.80 Spec. 14210 for Sch 80
              23720 Fungus Proofing

*Not supplied if insertion depth is less that 15".

 

CHARTS A & B - ELECTRICAL CIRCUITS AND RATINGS

SWITCH TYPE
SWITCH ACTION
ELECTRICAL RATINGS IN AMPS
ORDERING CODE
AC
DC
SINGLE STAGE
120V
240V
440V
30V
125V
250V
CHART A 
Mercury Contacts
SP-ST open on level FALL
10
5
3†
 
10
5
-4821
SP-ST open on level RISE
10
5
3†
 
10
5
-4820
SP-DT one switch
4
2
1†
 
4
2
-4810
SP-DT two switches E.I.*
10
5
3†
 
10
5
-4815
DP-ST two switches E.I.* open on level FALL
10
5
3†
 
10
5
-4813
DP-ST two switches E.I.* open on level RISE
10
5
3†
 
10
5
-4814
DP-DT two SP-DT switches
4
2
1†
 
4
2
-4806
CHART B 
snap action contacts
SP-DT one switch
12
5
3†
 
0.5**
0.25**
-7810
DP-DT two SP-DT switches
12
5
3†
 
0.5**
0.25**
-7806
SP-DT one hermetically sealed switch
5
5
 
5**
 
 
-7810HM
DP-DT two hermetically sealed SP-DT switches
5
5
 
5**
 
 
-7806HM
DP-DT two SP-DT switches
10
3
 
 
10‡
3‡
-9806
SP-DT one switch
10
3
 
 
10‡
3‡
-9810

†Available on special order, change 1st digit in ordering code from 4 to 5 or 7 to 8, i.e., -4820 becomes -5820, -7810 becomes -8810, etc.
‡10 amp inductive (polarized) at 125 VDC.
*Electrically Independent.
**Resistive.

Minimum Specific Gravity: Dependent on float size and rod length. See Dimensional Drawing.
Switch Type: Snap action or mercury. See Electrical Circuits and Ratings on Model Chart page.
Electrical Rating: See Electrical Circuits and Ratings on Model Chart page.
Wiring Connection: G, WT or E enclosure, terminal board. EV enclosure 18" (460 mm) leads.
Enclosures: G: painted steel and aluminum; WT: painted steel, aluminum and neoprene; E: aluminum; EV: aluminum and neoprene.
Wetted Parts: See Model Chart.
Approximate Weight: 301G, WT with 4-1/2" SS float, 8 ft. rod, 5" 125# cast iron flange: approximately 35 lb (16 kg) with E, EV enclosure: 39 lb (17.7 kg).