Profile cover photo
Profile photo
NuWave Technologies Inc.
6 followers -
Creatively designed hardware and software industrial control products.
Creatively designed hardware and software industrial control products.

6 followers
About
Posts

Post has attachment

Post has attachment
4-20 MA SOLID STATE RELAY SSR PULSE MODULE

The SSRMAN-1LP #4-20MaSolidStateRelay driver provides 0-100% PWM of any standard SSR.  The   of the time proportioning is 350mS at the center but gets longer toward the end of the range to optimize the resolution of the output of the #4-20Ssr system.  The calibration of the  can be adjusted by ordering option -ZS (zero and span pots). The SSRMAN-1LP can drive up to 4.2V @14mA offering a high performance, low cost solution to #4-20mASsr systems.
Photo
Add a comment...

Post has attachment
MEASURING THE TRUE RMS CURRENT IN PHASE ANGLE CONTROLLED LOADS

Most #CurrentTransformers  suffer from severely inaccurate measurements of the load current in phase angle controlled loads. This is because they tend to respond mainly to the peaks of the signal which have little to do with the actual current present in the load circuit.  A #TrueRMS  analysis of the current waveform is required to get an accurate value.

Our #NWCT is a True RMS #CurrentTransducer that can be ordered as 0-10V or 4-20mA output. The output is proportional to the current in the conductor passed through the sense transformer. The advantage to the NWCT is that it can sense distorted sinusoidal signals such as phase control and provide a True RMS output of the signal. The NWCT Current Transformer uses the latest in signal processing technologies to provide true RMS 4-20mA or 0-10V output of distorted AC current signals such as #PhaseAngleControlled  Loads.
Add a comment...

Post has attachment
NUWAVE INTRODUCES MICROTC TINY TEMPERATURE CONTROLLER

Our new MicroTC is the #SmallTemperatureController   our product line. The MicroTC #TemperatureController   is factory set for your setpoints and hysteresis.  A version is available with setpoint adjustment from an external potentiometer.  MicroTC is available in 12V and 24V versions and provides a 3 Amp MOSFET output that can be used to drive an SSR ( solid state relay) or small heater.  The integral solid state temperature sensor eliminates the cost of an external thermocouple or RTD.
Photo
Add a comment...

Post has attachment
NuWave Introduces Low Cost RC Snubber for SSRs

Introducing the new RCSB RC snubber board for Solid State Relays SSRs.


The RCSB #RCSnubber   suppresses dV/dt and provide reliable commutation. This is epecially important when controlling transformer coupled loads as improper commutation can result in huge inrush currents and blown fuses.  The RCSB snubber is also used on our #SCRPowerControl  assemblies.  The RCSB is available in 120, 240, 480 and 600VAC versions.

The RCSB Snubber Board mounts directly on the output terminals of a #SolidStateRelay. The RCSB provides overvoltage protection from transients and limits dV/dt.
Add a comment...

Post has attachment
NuWave Introduces New Current Limit Phase Angle Controller Module SSRMAN-1P-CL
        
The new #SSR Mounted #PhaseAngle Controller Module SSRMAN-1P-CL mounts directly on the SSR input terminals and provides true linear power phase angle control of the load. The output power is based on the command input and the current feedback from the current transformer. The command can be dip switch selected from over seven different industry standard inputs. Using the SSRMAN-1P-CL #CurrentLimit  the appropriate SSR for your load will provide a modular high isolation SCR power control at a very low price.  An extensive filtering scheme and proprietary zero cross detection algorithm improves noise rejection without sacrificing accuracy.
Add a comment...

Post has attachment
NuWave Technologies Introduces new low cost SCR gate driver

The new NWZC-SCR, is a low cost #SCR driver for driving back to back SCRs in resistive load applications.  The #SCRDriver board is zero cross fired and has on board MOV protection.  It provides optically isolated 5V, 24V inputs that can easily be interfaced to temperature controllers and PLC Time Proportiong (PWM) outputs.  The packaging is available in panel mountable or din rail mountable snap tracks.



SCRs requiring 200mA of gate current or less are a good fit for use with the NWZC-SCR.  Wiring of the Module is simple and requires no external power supply; the gate drive power is derived from the line supply of the SCRs.


 
Add a comment...

Post has attachment
Controlling #TECs ( #Pelteir ) Modules with Standard Temperature Controllers using the TCH1560

Controlling TECs or Thermo Electric Coolers with standard off-the-shelf temperature controllers presents a challenge to the system designer.  Pelteir devices require H-bridge drivers to provide heat and cool functions.  The H-Bridge has to be designed to allow the heat and cool outputs of the temperature controller to steer the correct polarity of the DC power source into the TEC.  The new TCH1560 Isolated H-Bridge Amplifier makes the design task much simpler.

TCH1560 TEC Pelteir Controller

The temperature controller outputs interface directly to the optically isolated input as shown above.  The power input is connected to the TCH1560 and the TEC is connected to the output.  Special shoot through prevention logic prevents the outputs from turning on at the same time even if both temperature controller outputs are on.  With a frequency response time as fast as 1mS and a 60V 15Amp rating the TCH1560 presents a high performance and economical way to drive TECs in a heat cool configuration.
Add a comment...

Post has attachment
Phase Fired SCRs and Line Harmonics

Phase Fired SCRs can generate significant 3rd, 5th & 7th order harmonics above the line frequency due to the thyristor firing occurring between the AC zero crossings:

When Phase Fired SCRs must be used due to the load characteristics described in our previous blogs, EMI filtering can be added to the line to attenuate the harmonics.  Several companies makes suitable high current filters for Phase Fires SCRs:

http://www.filterconcepts.com/ac_filters.html

http://www.schaffnerusa.com/components-group/emi-filters.php?gclid=CIj6x_O8660CFSEQNAodoE1J6A

http://www.schurterinc.com/content/view/full/25502/(language)/eng-GB

By using the line filters with Phase Fired SCRs it is still possible to obtain suitable EMC performance and allow sales with a CE mark.
Add a comment...

Post has attachment

Let’s Talk About Thyristor (SCR, TRIAC and SSR) Snubbers

Commutation Problems: When an #SCR or TRIAC is used to control an inductive load, the load current lags the mains voltage. When the device turns off at zero current, the rate of rise of the reapplied voltage can retrigger the device and produce half cycling and blown fuses. To limit this rate of rise and obtain reliable commutation, an R-C (resistor–capacitor) #Snubber circuit should be connected in parallel with the SCR/TRIAC.
dv/dt   Problems: When voltage transients occur on the mains supply or load of an SCR/TRIAC it can cause the device to turn on unexpectedly due to the fast rate of rise of voltage (dv/dt). This can result in false firing and half cycling of the load that can cause blown fuses when driving inductive loads. An R-C snubber circuit will help to limit the dv/dt seen by the device and will produce more reliable #thyristor firing.
#Snubber Suppliers: Although most designers use an empirical approach to solving the aforementioned issues with snubbers, a number of great articles have been published on the mathematical basis for calculating snubber circuit values

Check out our new RCSB Snubber: RCSB SNUBBER
Snubber Sizing: When an SCR/TRIAC using an R-C snubber turns on, the capacitor is discharged through the resistor into the device resulting in high peak currents. It is critically important when sizing your snubber to make sure that the resistor value does not become so low that the ratings of the SCR/TRIAC are exceeded when the capacitor is discharged.
 
#MOVs and TVSs: Metal Oxide Varistors and Transient Voltage Suppressors are both used on TRIACS/SCRs to “clamp” voltage spikes that can occur across the devices and damage them. Snubbers are not a substitute for MOVs/TVSs and vice versa. Snubbers and MOVs/TVs should be used together to get reliable performance and long life from the SCR/TRIAC application.
Solid State Relays (SSRs): AC output SSRs use either SCRs or TRIACS internally, so this information applies to them as well. Even though many #SSRs have internal #SnubberNetworks , we have found these to be insufficient for use in many inductive load applications. The addition of external properly sized snubbers has improved performance in many applications we have encountered when using our Solid State Relay Modules and SSRs for driving inductive loads.
Add a comment...
Wait while more posts are being loaded