We now offer BUNA-N (Nitrile rubber) float switches which allows us to offer our Intrinsically Safe Drum Alarm with protected guard again (!) We came up with the idea back in January to enclose our miniature PTFE float switches and it worked, however the PTFE float switches were too heavy for many liquids. The Specific Gravity of the BUNA float switch is only 0.5. As a general rule of thumb, BUNA-N is good for fuels, oils, solvents but is attacked by ketones, ester, aldehydes.See our chemical compatibility chart.
The guard enclosing the float is useful for filling operations where the Drum Alarm is being transferred frequently between drums. (using the 3/4 inch bung) Our customers have found that the guard is essential to protect the float switch. Complete information about this product IS-DHK-SB on this page.