Kenco Engineering NFS No-Flow Safety Switch User Manual
Kenco engineering company
KENCO ENGINEERING COMPANY
P.O. BOX 470426, TULSA, OK 74147-0426
PHONE: (918) 663-4406 FAX: (918) 663-4480
http://www.kenco-eng.com
e-mail:
INSTALLATION & OPERATIONS MANUAL
FOR NO-FLOW SWITCHES
1. Switch MUST be mounted either vertically (terminal end up) or at a minimum angle of 20 º
off horizontal with terminal end at the high point. This prevents water from accumulating around
switch contact.
2. A 25 micron sintered bronze or similar in-line type filter should be installed ahead of the No-
Flow switch. These are available from either KENCO or most manufacturers of lubricators.
3. To assure constant oil viscosity, mount switch in a warm place near cylinder lube-line check
valve or point of lubrication. The "NFS-4", "NFS-5" and "NFS-9" No-Flow switches for Ajax
are provided with brackets for mounting to one of the screws which hold the cast cover to the
cylinder near the cylinder check. Connect No-Flow switch contact wire to magneto or
alarm/shutdown switch.
4. Connect line from lubricator to inlet port on No-Flow switch.
5. Hand pump lubricator until oil flows from outlet port; then connect line from outlet to point
of lubrication.
6. Switch is factory adjusted for a shutdown time of approximately 3 minutes using SAE 30 oil
at 100 º F. The switch is viscosity sensitive, therefore, shutdown time will vary with oil viscosity.
Switch can be field adjusted for a shutdown time between 2-8 minutes.
7. If adjustments are necessary, ensure that adjustments are made while engine / compressor /
No-Flow switch are at their normal operating conditions. The adjustment setscrew is located on
bottom of switch housing. Turn setscrew IN to decrease shutdown time and OUT to increase
shutdown time. Shutdown time can be determined by removing/disabling lubricator pumping
unit. On multiple pump installations pumping at the same rate, the setting can usually be
transferred from one switch to another by making the distance from the end of the adjustment
setscrew to the end of the adjustment setscrew housing equal on all switches.