Archive for January, 2010
Over the years sequencing different stages for compressors, staged electric heat strips, actuators, pumps, and various lighting applications has not been the easiest job for the mechanic. Functional Devices, manufacturers of the famous Relay In a Box (RIB relays), has released the RIBMN24Q4C-PX programmable sequencer to make your job easier.
The RIBMN24Q4C-PX is used to control four integrated 15 amp SPDT relay contacts with one (0-10vdc) analog signal. Power input of this control is 24 VAC/DC. Unlike other models, the RIBMN24Q4C-PX has an on-board digital display to eliminate the need to attach a voltage meter. Just dial up your desired trip voltage and move on to the next relay set point!
Features:
Relay will activate when control signal voltage reaches or exceeds individual relay setpoint
Turn Off is set to 200mV less than setpoint
Factory relay setpoints: Can be changed by installer
Relay 1: 3V » Relay 3: 7V
Relay 2: 5V » Relay 4: 9V
Minimum setpoint: 0.5V
Maximum setpoint: 9.9V
Relay number will flash 3 times when voltage exceeds setpoint
Pressing UP or DN button in normal run mode will display the voltage present on Analog Input
*Sequencer can be piggy-backed, allowing more than 4 relay setpoints if sequencer 1 and sequencer 2 are using the same power control input and input signal source. At this point the relay setpoints on sequencer 2 can be different or the same as sequencer 1. Note: sequencer requires 5va power draw per sequencer from control transformer.
The RIBMN24Q4C-PX is also shipped with a MT212-6 din rail mounting strip.
If you are a Stromquist customer located in Georgia or Florida you can order this product at www.stromquist.com. All others can order this product from one of our affiliates at CGNA.
2-way valves are pretty simple and straight-forward. A 2-way valve is any type of valve with two ports: an inlet and an outlet port, typically labeled “A” and “AB” respectively. 2-way valves are used in many applications, from basic on/off to more complex variable flow applications with pumps and VFDs. The type of valve you need for an application depends on the amount of flow, the degree of control, shut-off, and pressure drops over the valve.
3-way valves have, yes, three ports, labeled “A”, “B”, and “AB”. Port “AB” is common to the “A” or “B” port. 3-way valves are commonly found in constant flow/volume pumping systems and can be either mixing or diverting valves. 3-way valves can be piped in the supply or return. If in the supply, then a diverting valve is used. If piped in the return, a mixing valve is used. Ball valves can be piped to be mixing or diverting, but globe valves require different bodies for mixing or diverting.
Mixing applications have the 3-way valve configured with two inputs from the supply piping and one output to the return piping, thus mixing together two inputs before sending it out. Mixing valves are most commonly used with modulating control but can be on/off.
Diverting applications have the 3-way valve configured with one input from the supply side and two outputs to the return piping. In general, diverting valves are more expensive than mixing valves.
Eric interviews the very interesting Pete Baselici from Watt Stopper, one of the world's leading manufacturers of lighting controls. Topics include: Watt Stopper's newest products, "ladderless" commissioning,
Read MoreDue to difficulties in obtaining some machined components and because of declining sales, the M&M Series 150E Low Water Cut-Off and all its variants are being discontinued as of December 31, 2009. This will impact the 150E, 1507E, and replacement heads for those products.
M&M recommends the Series 150S float style Low Water Cut-Off as a direct replacement for the 150E and the new 1575 as an alternative for clients that wish to continue using a probe-style device.
From a replacement parts perspective, the 150S replacement head will bolt directly to an existing 150E body. Some minor wiring modifications may be required, and the user should be aware that the time delays and the pump differential are not adjustable on the 150S. Keep in mind that it is also good practice to use a relay between the 1501S and the boiler feed pump.
The latest accurate information and demos on products
