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Replacement/Crossover of Mercury Relay Contactors

Crydom 3RHP Series, AC Input, 3 Phase Hybrid Solid State Contactor, 40-50 Amp Output, (280 or 600 VAC (A replacement for Mercury). Solid state and mechanical switching technologies are combined to provide the performance advantages of both technologies in the industry standard DP contactor package. Crydom 3RHP Series, DC Input, 3 Phase Hybrid Solid State Contactor, 40-50 Amp Output, (120 or 240 VAC) (A replacement for Mercury). Solid state and mechanical switching technologies are combined to provide the performance advantages of both technologies in the industry standard DP contactor package.
Crydom 1RHP Series, AC or DC Input, 1 Phase Hybrid Solid State Phase Contactor, 20 Amp Output, (90-250 VAC) (A replacement for Mercury). Solid state and mechanical switching technologies are combined to provide the performance advantages of both technologies.  No heat sink required, DIN rail mount. HBControls Solid State Relay and Heat Sink Assemblies. Convenient DIN rail mounting configuration, finger-safe covers and utilize the highest quality relays available.
Chromalox 4003 DIN-Rail Mount Three Phase Power Controller. (A replacement for Mercury Contactors/Relays), Three Phase Loads up to 60 Amps, 575 Vac, 9-35 Vdc, 100-240 Vac or 24 Vac Input Signals, Easy DIN-Rail or Sub-Panel Installation, Size Compatible for Easy Replacement of Mercury Displacement Relays, Optional Integral Heatsink Thermostat.

Crossovers from DuraKool Mercury Relays

DuraKool Part # Description HBControls Item ID #'s HBControls Part # HBControls Series
1035A120AC (Coil Voltage: 120 volts AC - 1 Pole - Normally Open - 35 Amp) HBC10112
HBC-690CHAA   (DIN Rail Mount)
HBC-690CHAA-PM (Panel Mount Option)
40 Amp Single Pole 90-280Vac Control
2035A120AC (Coil Voltage: 120 volts AC - 2 Pole - Normally Open - 35 Amp) HBC10111
HBC-690CHAA-2  (DIN Rail Mount)
HBC-690CHAA-2-PM   (Panel Mount Option)
40 Amp 3ph/2pole  90-280Vac Control
3035A120AC (Coil Voltage: 120 Volts AC - 3 Pole Normally Open - 35 Amp) HBC10116
HBC-690CHAA-3-PM   (Panel Mount Option)
40 Amp 3ph/3pole  90-280Vac Control
1035A24AC (Coil Voltage: 24 Volts AC - 1 Pole Normally Open - 35 Amp) HBC10131
HBC-50HAL-E   (Din Rail Mount)
HBC-50HAL-E-PM  (Panel mount)
40 AMP Single Pole 24VAC Control
2035A24AC (Coil Voltage: 24 Volts AC - 2 Pole Normally Open - 35 Amp) HBC10132
HBC-50HAL-2-E   (DIN Rail Mount)
HBC-50HAL-2-E-PM (Panel Mount)
40 AMP Double Pole 24VAC Control
3035A24DC (Coil Voltage: 24 Volts DC - 3 Pole Normally Open - 35 Amp) HBC10135
HBC-690CHDA-3   (DIN Rail Mount)
HBC-690CHDA-3-PM  (Panel Mount)
40 Amp 3ph/3pole 4-32VDC Control
2060APS120AC (Coil Voltage: 120 volts AC - 2 Pole - Normally Open - 60 Amp) HBC10123 HBC-90AF2B (standard Panel Mount with 120V Fan) 80 Amp 3ph/2pole 90-280V Control
3060APS120AC (Coil Voltage: 120 volts AC - 3 Pole - Normally Open - 60 Amp) HBC10125 HBC-90AF3B  (standard Panel Mount with 120V Fan) 80 Amp 3ph/3Pole  90-280Volt Control

Crydom  Hybrid Solid State Contactors

Solid State Relays and Contactors (SSRs) have been available in one form or the other for over 40 years. Traditional Electromechanical Relays and Contactors (EMRs) as well as Mercury Displacement Relays and Contactors (MDRs) have been available even longer. However, current Environmental regulations now make the future use of Mercury Contactors problematic, and Electro Mechanical Contactors may not offer the required life expectancy or operational characteristics to be suitable replacements for MDRs. Crydom, a world class supplier of Solid State Relays and Controls, has introduced the 3RHP family of Hybrid Solid State Contactors to address this market need for both existing applications and new designs.  The 3RHP’s hybrid technology combines the benefits of both SSR and EMR technologies in a unique approach resulting in a Hybrid Solid State Contactor with ratings of up to 50Amps @ 600VAC.

What is a Hybrid Solid State Contactor?

Crydom has combined solid state and mechanical switching  technologies to create its line of Hybrid Solid State Contactors. The RHP contactors (patent pending) provide the performance advantages of both technologies in an industry standard DP contactor package. Crydom’s proven Hybrid SSR technology utilizes contactless solid state turn on and turn off performance, coupled with the very low on state power dissipation characteristic of contactors. This combination results in a fast switching highly reliable contactor that does not require the use of a heat sink.

Available in single and 3 phase versions, Hybrid Solid State Contactors are a cost effective alternative to Mercury Displacement Relays (MDR). RHP contactors are safe and comply with industry standards while offering high power switching capabilities.

What are the advantages of the RHP contactors?

Crydom combined solid state and mechanical switching technologies to create its line of Hybrid Solid State Contactors:

The Hybrid Contactor (3RHP) offers the following advantages:

Mercury and Mechanical Vs. Solid State Relays:

Mercury:          Solid state:      EMR:

Contains no mercury                                                               No                   Yes                  Yes
Provide air gap isolation:                                                        Yes                  No                   Yes
Photo-coupled isolation of input to output                             No                   Yes                  No
Can accommodate high inrush well                                        Yes                  Yes                  No
Does not have arcing                                                              Yes                  Yes                  No
Quiet operation                                                                       Yes                  Yes                  No
Silent operation                                                                       No                   Yes                  No
Environmentally friendly                                                        No                   Yes                  Yes
Can be mounted at any angle                                                 No                   Yes                  Yes
Does not produce heat or require a heat sink                          Yes                  No                   Yes
Available as a hybrid                                                              No                   Yes                  Yes
Can be used in hazardous environments                                 Yes                  Yes                  Yes
Extremely fast switching                                                        No                   Yes                  No
Is well suited for proportional power control                         No                   Yes                  No
Can be used for phase angle control                                       No                   Yes                  No
Can be exported to other countries easily                               No                   Yes                  Yes
RoHS                                                                                      No                   Yes                  Yes
Millions of operations                                                             Yes                  Yes                  No
Billions of operations                                                             No                   Yes                  No
Contains no moving parts                                                       No                   Yes                  No
Little to no leakage current/voltage w/o snubber                    Yes                  Yes                  Yes
Has input currents as low as 2 mA                                         No                   Yes                  No
Has no inrush on input terminals                                            No                   Yes                  No
Current limited control input available                                   No                   Yes                  No
Fast switching time                                                                 No                   Yes                  No
Easily disposed of                                                                   No                   Yes                  Yes
Consumes minimal power, Input side                                     No                   Yes                  No
Consumes minimal power, output side                                   Yes                  Yes                  Yes
Consumes no power on output side                                        Yes                  No                   Yes
Can be used in variable power applications to save energy    No                   Yes                  No
Risk of fines due to improper handling and disposal             Yes                  No                   No
Universal acceptability globally                                              No                   Yes                  Yes
Easily compatible with industrial control components           No                   Yes                  Yes
Finger safe operation                                                              No                   Yes                  Yes


We are frequently asked to recommend our solid-state relay assembly in replacement of a mercury or electromechanical relay or contactor. Often the only application information provided is the contact rating of the relay currently being used, while this information is helpful it is incomplete. It is imperative that the actual load being controlled, and the ambient operating temperature is known when applying a solid-state relay.

Solid-state relays, unlike mercury or electromechanical relays, do not have moving parts which wear out due to mechanical wear over a finite number of operations, theoretically, when properly applied, they infinite life. It is important therefore, that in addition to the current and voltage all characteristics of the load are considered. Is the load resistive or inductive, AC or DC, three phase or single phase. If three phase, are all three or only two legs being controlled, is the circuit Delta or Y? A major enemy of the solid-state relay and often the cause of premature failure is heat, when the relay is switching a load it is generating an amount of heat proportional to the wattage of that load.

When replacing a mercury or electromechanical relay with a solid state relay make sure that you have determined the actual load being switched as well as the ambient temperature of the environment in which the relay is being operated. Generally, if the load is greater than 10 amperes AC and the ambient temperature is greater than 20 degrees centigrade the relay must be mounted on an appropriately sized heat sink, or another method of directing heat away from the relay utilized. In the case of larger current loads, or a higher ambient temperature, both a heat sink and cooling fan may be required to direct heat away from the assembly.

HBControls engineers are well versed in the practice of determining the appropriate combination of solid-state relay and heat dissipating devices.

How to Choose the Solid State Relay That is Right for Your Application.
  0 .01 .04 .06 .10 .15 1.5 2.0 3.0 5.0 10 15 20 25 30 40 50
3 - 10 VDC
0-60VDC, 600 PIV, NR
0-60VDC, 600 PIV, NR
3 - 15 VDC
12-280VDC, 600PIV, NR
48-530VDC, 1200 PIV, NR
3 - 32 VDC
24-280VAC, 600PIV, NR
      HBC-11-D2W203 24-280VAC, 600PIV, NR                  
24-280VAC, 600PIV, SR
    HBC-25D 24-280VAC, 600PIV, SR HBC-25HD 48-530VAC, 1200PIV, SR HBC-625HD 48-660VAC, 1200PIV, SR            
    HBC-50D 24-280VAC, 600PIV, SR
48-530VAC, 1200PIV, SR
48-660VAC, 1200PIV, SR
    HBC-25DA 24-280VAC, 600PIV, SR HBC-25HDA 48-530VAC, 1200PIV, SR          
    HBC-50DA 24-280VAC, 600PIV, SR
48-530VAC, 1200PIV, SR
48-660VAC, 1200PIV, SR
    HBC-90DA 24-280VAC, 600PIV, SR
48-530VAC, 1200PIV, SR
48-660VAC, 1200PIV, SR
        HBC-T50DK 48-530VAC, 1200 PIV, TP (Ratings are per Pole)      
        HBC-90HDK-2 48-530VAC, 1200 PIV, TP
(Ratings are per Pole)
4 - 10 VDC
  HBC-11-CX241 12-280VAC, 600 PIV, NR                      
4 - 15 VDC
            HBC-D25HDA 48-530VAC, 1200PIV, DR - (Ratings are per Pole)            
48-530VAC, 1200PIV, DR (Ratings are per Pole)
4 - 31 VDC
    HBC-25CDA 24-480VAC, 600 PIV, SW HBC-25CHDA 48-530VAC, 1200 PIV, SW          
    HBC-50CDA 24-480VAC, 600 PIV, SW
48-530VAC, 1200 PIV, SW
HBC-650CHDA 48-660VAC, 1200 PIV, SW
    HBC-90CDA 24-480VAC, 600 PIV, SW
48-530VAC, 1200 PIV, SW
48-660VAC, 1200 PIV, SW
15 - 32 VDC
        HBC-11-CXE240D5 12-280VAC, 600 PIV, NR                
        HBC-11-CXE380D5 48-530VAC, 600 PIV, NR                
          HBC-D25HEA 48-530VAC, 1200 PIV, DR - (Ratings are per Pole)            
          HBC-D40HEA 48-530VAC, 1200 PIV, DR - (Ratings are per Pole)          
18 - 36 VAC
      HBC-11-CXE240A5 12-280VAC, 600 PIV, NR                
90 - 140 VAC
12-280VAC, 600 PIV, NR
    HBC-25CAA 12-280VAC, 600 PIV, SW HBC-25CHAA 48-530VAC, 1200 PIV SW          
    HBC-50CAA 12-280VAC, 600 PIV, SW
HBC-50CHAA 48-530VAC, 1200 PIV SW HBC-650CHAA 48-530VAC, 1200 PIV, SW
    HBC-90CAA 12-280VAC, 600 PIV, SW
48-530VAC, 1200 PIV SW
48-530VAC, 1200 PIV, SW
90 - 280 VAC
24-280VAC, 600PIV, SR
    HBC-25A 24-280VAC, 600PIV, SR HBC-25HA 48-530VAC, 1200 PIV, SR HBC-625HA 48-660VAC, 1200 PIV, SR            
    HBC-50A 24-280VAC, 600PIV, SR
48-530VAC, 1200 PIV, SR
48-660VAC, 1200 PIV, SR
    HBC-25AA 24-280VAC, 600 PIV, SR HBC-25HAA 48-530VAC, 1200 PIV, SR          
    HBC-50AA 24-280VAC, 600 PIV, SR
48-530VAC, 1200 PIV, SR
48-660VAC, 1200 PIV, SR
    HBC-90AA 24-280VAC, 600 PIV, SR
48-530VAC, 1200 PIV, SR
48-660VAC, 1200 PIV, SR
        HBC-T50AK 48-530VAC, 1200 PIV, TP      
        HBC-90HAK-2 48-530VAC, 1200 PIV, TP
  0 .01 .04 .06 .10 .15 1.5 2.0 3.0 5.0 10 15 20 25 30 40 50
1. Select the Load Current to be Switched and the Input Range of the Controller.
Find the Current Load to be switched (horizontal axis) right, and follow it down to the appropriate Controller Input Range (vertical axis).
2. Select Model Numbers with Correct Voltage Range and Peak Volts.
Find the Model Numbers available paying close attention to Voltage Range, Peak Maximum Volts and Style of Relay.

SR=Standard Relay, Lug Terminals
NR=Narrow Relay, <.5" Wide, Stripped Wire Terminals
DR=Dual Relay, .187" Faston Terminals
TP=3-Phase Relay, Lug Terminals
Stripped Wire Terminals

Home ] Up ] Chromalox 4466/4468 Contactor Temperature Control Panel ] Crydom 3RHP Series AC or DC Control Replacement for Mercury Relays ] Crydom 1RHP Series AC or DC Control Replacement for Mercury Relays ] Crydom 3RHP Series DC Control Replacement for Mercury Relays ]

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5880 Alpine Ave. NW - Comstock Park, MI 49321  USA
Tel 616-784-1121 - 800-442-2581 - Fax 616-784-7775

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