2
PENBERTHY
MODEL MGS-314L SERIES LEVEL CONTROL SWITCH
INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
2 SPECIFICATIONS/APPROVALS
2.1 Enclosure
Watertight (Type 4) and Explosion-Proof (Type 7) 316 STS housing
2.2 Switch
Output:
MGS-314L Series: SPDT (Form C) switch output: 1 AMP Maximum Switching Current, 150 VDC
Maximum Switching Voltage non-inductive load, 25 Watts - Maximum power
Repeatability:
Better than 0.032" (0.81 mm)
Response time:
<100 milliseconds
Operating temperature:
-40°F to 225°F (-40°C to 107°C) with third party approvals
Ambient temperature:
-4°F to 104°F (-20°C to 40°C) with third party approvals
Dead band:
0.5" (13 mm)
2.3 Approvals
MGS-314L-C
CSA Approved Ex d
Explosion-proof for: Division 1;
Class I; Groups B, C, D
Class II; Groups E, F, G
Class III; Type 4
When installed in accordance with control
drawing 7E741-008 (Figure 2)
MGS-314L-C
CSA Approved
Intrinsically safe for: Division 1;
Class I; Groups B, C, D
Class II; Groups E, F, G
Class III; Type 4
When installed in accordance with control
drawing 7E742-008 (Figure 3)
MGS-314L-A
ATEX and IECEx approved by CSA
Flame-proof for: Ex db IIB T5 Gb
1 A Max or 150Vdc Max
*Must use suitably certified minimum Ex db IIB
conduit seal
When installed in accordance with control
drawing 7E741-010 (Figure 4)
MGS-314L-A
ATEX and IECEx approved by CSA
Intrinsically safe for: Ex ia IIC T5 Ga
When installed in accordance with control
drawing 7E742-010 (Figure 5)
3 THEORY OF OPERATION
While reading the theory of operation refer to
Figure 1 for the location of the components.
The description is based on a side view.
With the liquid level below the switch, the reed
should be at position 'A'. The reed is held in
this position by a magnetized stop. As the float
ascends and passes the switch, it induces a
magnetic field in the reed. The reed is coupled
to the float and moves with it until contact with
the opposite stop is made. The magnetized
stop then holds the reed in its new position.
The movement of the reed causes the switch to
change state.
As the float descends with the liquid level it
passes the switch and the process described is
reversed. This returns the switch to its original
state.
FIGURE 1
MGS-314L switch positions
Position A
Position B
