Welch Vacuum 2511B-76, C-75, C-76, C-77Aspiration/Filtration - Manual (Page 7)

2.60 Electrical Power
2.61 Power Source Review
Review the power source and the motor rating to be sure they agree in voltage, phase, and frequency.
Serious damage may occur to the motor if it is connected to an improper voltage. All Welch pumps must
be grounded. Grounding reduces the risk of electric shock in the event of an electrical short circuit. The
plug must be plugged into a properly grounded outlet. Consult your local electrical codes if you have
doubts.
2.62 Servicing of Double-Insulated Product
In a double-insulated product, two systems of insulation are provided instead of grounding. No grounding
means is provided on a double-insulated product, nor should a means for grounding to be added to the
product. Servicing of a double-insulated product requires extreme care and knowledge of the system and
should be done only by qualifi ed service personnel. Replacement parts for the double-insulated product
must be identical to those parts in the product.
2.63 Classifi cation And Symbol Glossary
Double Insulated
OFF (Power)
ON (Power)
2.70 Vacuum Connection
2.71 For best results, Welch recommends the length of the tubing between the pump and the chamber be kept
as small as possible.
2.80 Vacuum Gauges
2.81 All Aspiration/Filtration Vacuum Systems come with dial vacuum gauges. The vacuum gauge gives
negative pressure - That is pressure below atmospheric. The reference point for the gauge is
atmospheric pressure.
2.90 Traps
2.91 The need for a Trap
Model 2511 pumps are resistant to moisture-induced corrosion. The collection vessel has a fl oat valve is
attached to the regulator assembly to prevent water condensate from accidentally being ingested into the
pump. An in line hydrophobic fi lter provides further protection against moisture ingestion.
WARNING
The pump is not recommended for pumping acid, base or organic vapors
or gases. Serious damage to the pump will shorten the pump’s service life.
In addition, pumping fl ammable vapors or gases can lead to serious safety
hazard leading to fi re or explosion.
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