| No-Feed Detector
| For the safest automatic pumping, the No-Feed Detector is recommended. | The YOKOTA No-Feed Detector is a safety device to prevent the pump from dry operation. Reacting to the movement of the check valve, the switch cuts off power automatically when the amount of flow is close to zero. If your pump is equipped with the Non-Water Hammer Check Valve with the No-Feed Detector, there is no need to worry about the occurrence of water hammer even if a high pressure tank is installed near the pump. Your automatic pumping system will operate safely and reliably. |
NP model
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BP model
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| NP model (For SL-SN, SH) | | 
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| Part name | Part name | | 41-1 | Proximity switch | 31-1 | O-ring | | 41-2 | Proximity member | 31-2 | O-ring | | 41-3 | Case | 1 | Valve case | | 41-4 | Support ring | 13 | Valve arm pin | | 41-5 | Cap | 19 | Pin holder | | 41-6 | Set screw | 30-1 | O-ring |
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| Use a flow speed of 0.38m/sec as a guideline for minimum flow rate setting.
However, use 120L/min as a minimum value for SNP-50, and 180L/min as a minimum value for SNP-65, 80. |
| When not operating for long periods of time during winter, remove the cap (41-5) and drain the water in the cap (or take measures to prevent the No-Feed Detector from freezing.) |
| BP model (For SL-NB) | | 
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| Part name | Part name | | 41-1 | Case | 41-80 | Proximity switch | | 41-2 | Cover | 41-90 | Set screw | | 41-3 | Adjusting nut | 41-10 | Stopper | | 41-4 | Coil spring retainer | 41-11 | Retainer | | 41-5 | Proximity tip | 31-20 | O-ring | | 41-6 | Cap | 31-30 | O-ring | | 41-7 | Coil spring | 2 | Top cover |
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| Use a flow speed of 0.38m/sec as a guideline for minimum flow rate setting.
However, use 100L/min as a minimum value for NBP-40. |
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Contact protector relay | | The contact protector relay protects small capacity contacts of the proximity switch. Please install the contact protector relay, using the specifications below, in the control panel for the YOKOTA No-Feed Detector.
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| Power supply | AC 100V, 200V | | Control capacity | AC 7A-250V | DC 3A-30V |
| Connection and operation
, | Feed condition | No-feed condition | | Proximity switch | ON | OFF | | Contact protector relay | a contact | b contact | a contact | b contact | | ON | OFF | OFF | ON |
| Outline drawing
| Wiring diagram
 | If voltage is applied to an incorrect connection (parts T, H, and S), the proximity switch will be damaged. |
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Specifications stated here may be subject to change without notice due to product improvement.
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