Rotation Tester and AC Detector for Circulating Pumps etc

Very hand little device

This is a handy little tool for indicating electrically energized solenoids and motors as well as motor rotation on some types of pumps. It's made in Sweden by Geonordic and seems to work fine for indicating rotation with Grundfos brand circulator pumps, but not so much with the Taco 007 Series circulators pumps. I don't know if it because the magnetic field from the Taco motor is just too weak or if it is interference from the amount of cast iron in the pump motor housing and flange. With larger multi pump installations like you have in commercial boiler rooms, this little tool makes it easy to tell when the pump motor is energized when there is otherwise either too much background noise or vibration from other nearby equipment to hear or feel if the motor is running. It also works for determining the rotation of small shaded pole motors used in things like bathroom ventilator fans. You can see and feel the little red and white disc rotate inside the testers housing when it is placed in a magnetic field. It was a little expensive for such a small tool and it may not always sense the magnetic field from every small motor, but it is still a useful thing to have on your key chain.

I bought this to test the central heating pump in my boiler because I suspected it was defective. The tester didn't come with particularly helpful instructions, but if held in the position shown in the 2nd picture, the indicator dial rotated, so I assumed the pump was running.Upon further investigation, the pump did prove to be defective. It was running but at quite a slow speed. Using a multimeter, I found out that the "run" capacitor (located in the plastic box on top of the pump body) was faulty and read only 1.5 microfarads instead of the 2.5 microfarads shown on its label. With a new capacitor fitted, the pump was back to full strength and the tester began to rotate when held in the position shown in the 1st picture. It didn't do this with the defective capacitor in place.So a few things to note (when testing domestic central heating pumps):1. The rotation speed of the tester dial does not show the speed of the pump. A central heating pump rotates far more rapidly than the dial on the tester would indicate.2. I think the dial on the tester is reacting to the fluctuating magnetic field around the pump, and so is showing if the pump is energised, but may not necessarily indicate rotation. See bottom paragraph.3. With the defective capacitor still in place, the tester needed to be held right against the pump (2nd image) before the dial would rotate. With a healthy run capacitor, the tester detected the magnetic field from much further away (1st image).If I get the chance, I will have a go with another pump, while preventing the impeller rotating to see what the tester indicates in that case. I'll try and update this review.UPDATE: Well I have now had a go with a pump on the bench and the impeller prevented from turning. The dial on the tester still rotates, perhaps not quite as strongly as when the impeller is moving freely. Having tried this test I'm not confident that I could tell if a pump was stuck or not using the tester. Also: I have noticed that Amazon keeps swapping the order of these pictures so the 1st/2nd picture comments might be reversed.

Arrived broken, wouldn't spin !second time of complaint with out reply !!!

Awesome gadget leaving the guess work out of the issue.

When I went to use it a second time it didn't work

Good

Used this few times and proved it a couple of times by the old method of ensuring a pump in actually turning; very handy.