Cont ent ontent Solid state relay Type selection .......................................................................................... 8.2 Printed circuit board mount ................................................................... 8.6 Solid-state relay HM AC, DC ............................................................... 8.6 Solid-state relay HT AC ....................................................................... 8.8 Solid-state relay HQ AC ...............................................
Type selection 1-phase solid-state relays / Zero voltage switching AC Load voltage range 12 ... 275 VAC 24 ... 600 VAC 48 ... 530 VAC 48 ... 530 VAC 48 ... 530 VAC Load current range 5 mA ... 4 A 5 mA ... 5 A (25 A)* 5 mA ... 5 A (25 A)* 5 mA... 10 A 5 mA ... 10 A Control voltage range 4 ... 30 VDC 4 ... 14 VDC 8 ... 32 VDC 4 ... 14 VDC 8 ... 32 VDC Construction M T T Q Q Type HM D2704 HT D6005L HT D6005H HQ D6010L HQ D6010H Page 8.6 8.8 8.8 8.10 8.
Type selection 1-phase solid-state relays / Zero voltage switching AC Load voltage range 12 ... 280 VAC 12 ... 280 VAC 24 ... 600 VAC 12 ... 280 VAC 24 ... 600 VAC 24 ... 510 VAC 24 ... 600 VAC 24 ... 510 VAC 24 ... 600 VAC 12 ... 280 VAC 24 ... 600 VAC 24 ... 600 VAC 24 ... 600 VAC Load current range 5 mA ... 25 A 5 mA ... 25 A 5 mA ... 35 A 5 mA ... 50 A 5 mA ... 50 A 5 mA ... 50 A 5 mA ... 75 A 5 mA ... 75 A 5 mA ... 125 A 5 mA ... 25 A 5 mA ... 35 A 5 mA ... 50 A 5 mA ...
Type selection 1-phase solid-state relays / Zero voltage switching AC Load voltage range 12 ... 280 VAC 24 ... 600 VAC 24 ... 600 VAC 24 ... 600 VAC Construction D with heat sink ESG 8.4 Load current range 5 mA ... 25 A 5 mA ... 35 A 5 mA ... 50 A 5 mA ... 75 A Control voltage range 3,5 ... 32 VDC 3,5 ... 32 VDC 3,5 ... 32 VDC 3,5 ... 32 VDC Construction D D D D Type HD D2825K HD D6035K HD D6050K HD D6075K Page 8.22 8.22 8.22 8.
Type selection 3-phase solide-state relays / Zero voltage switching AC Load voltage range 24 ... 520 VAC 24 ... 520 VAC Load current range 3 x 5 mA ... 50 A 3 x 5 mA ... 50 A Control voltage range 8,5 ... 30 VDC 90 ... 240 VAC/DC Construction L L Type Page HL D5250 HL A5250 8.26 8.26 Construction L 3-phase solide-state relays / Zero voltage switching AC with heat sink Load voltage range 24 ... 520 VAC Load current range 3 x 5 mA ... 22 A Control voltage range 10 ...
Printed circuit board mount Solid-state relay HM • Control voltage range: 4 ... 30 VDC, 3 ... 30 VDC • Load voltage range: 12 ... 275 VAC, 2 ... 60 VDC • Load current range: 5 mA ... 4 A, 5 mA ...
Printed circuit board mount Solid-state relay HM Technical data Zero switching Instantaneous switching-on Control circuit Load circuit HM D2704 Yes – DC AC HM D0603D – Yes DC DC HM D6004 PG Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms/AC; 1s/DC) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I 2t for fusing (< 10 ms) 12 ...
Printed circuit board mount Solid-state relay HT • Control voltage range: 4 ... 14 VDC, 8 ... 32 VDC • Load voltage range: 24 ... 660 VAC • Load current range: 5 mA ... 5 A (25)* Dimensions 4 Output 3+ 2 1,5 x 1,5 24,5 Construction T Input HT D6005L HM D6005H 6,3 43,6 1 ø1 7,6 1,7 7,83 12,7 10,16 5,08 Thermal diagram 35 HKT 4.0 30 Full on state Power loss (W) 25 HKT 3.
Printed circuit board mount Solid-state relay HT Technical data Zero switching Instantaneous switching-on Control circuit Load circuit HT D6005L Yes – DC AC HT D6005H Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I 2t for fusing (< 10 ms) 24 ... 600 VAC 10 ... 800 Hz 1200 V 5 mA ...
Printed circuit board mount Solid-state relay HQ • Control voltage range: 4 ... 140 VDC, 8 ... 32 VDC • Load voltage range: 24 ... 600 VAC • Load current range: 5 mA ...
Printed circuit board mount Solid-state relay HQ Technical data Zero switching Instantaneous switching-on Control circuit Load circuit HQ D6010L Yes – DC AC HQ D6010H Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I 2t for fusing (10 ms) 24 ... 600 VAC 10 .... 440 Hz 1200 V 5 mA ...
Standard panel mount package, 1-phase Solid-state relay HS, zero voltage switch • Control voltage range: 3... 32 VDC, 20 ... 265 VAC/DC • Load voltage range: 12 ... 660 VAC • Load current range:5 mA ... 125 A Dimensions 28 ø4,3 max. 29 M5 Construction S 47,6 43,2 58,2 Thermal diagrams (all relays already have heat conduction foil) Max.
Standard panel mount package, 1-phase Solid-state relay HS , zero voltage switch Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HS D2825 Yes – DC AC HS A2825 Yes – AC/DC AC HS D6035 Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
Standard panel mount package, 1-phase Solid-state relay HS, zero voltage switch Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HS D2850 Yes – DC AC HS D6050 Yes – DC AC HS A5150 Yes – AC/DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
Standard panel mount package, 1-phase Solid-state relay HS, zero voltage switch Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HS D6075 Yes – DC AC HS A5175 Yes – AC/DC AC HS D51125 Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
Standard panel mount package, 1-phase Solid-state relay HS, instantaneous switch • Control voltage range: 3,5 ... 32 VDC • Load voltage range: 24 ... 510 VAC, 5 ... 110 VDC • Load current range: 5 mA ... 40 A Dimensions 28 ø4,3 max. 29 M5 47,6 43,2 5,1 7,5 58,2 Construction S 25,4 M4 45 Thermal diagrams (all relays already have heat conduction foil) Max. load current 35 A 60 1,5 K/W 50 Max. load current 20 A 1,1 K/W 60 0,75 K/W 56.25 50 2,1 K/W 56.
Standard panel mount package, 1-phase Solid-state relay HS, instantaneous switch Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state dv/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I 2t for fusing (10 ms) Max.
Standard panel mount package Solid-state relay HD • Control voltage range: 3... 32 VDC • Load voltage range: 12 ... 600 VAC • Load current range: 5 mA ... 75 A Dimensions 27,5 2M5 22,5 47,6 91 Construction D Ø8 max. 2 M4 x 20 Thermal diagrams Heat sinks see on pages 32, 33 and 34 Max. load current 35 A Max.
Standard panel mount package Solid-state relay HD Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HD D2825 Yes – DC AC HD D6035 Yes – DC AC HD D6050 Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
Standard panel mount package Solid-state relay HD Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HD D6075 Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I2t for fusing (10 ms) Thermal resistance to base 24 ... 600 VAC 0,1 ...
ESG 8.
DIN rail or panel mount with integrated heat sink Solid-state relay HD • Control voltage range: 3 ... 32 VDC • Load voltage range: 12 ... 600 VAC • Load current range: 5 mA ... 35 A Dimensions 112 93 22,5 47,6 91 2M5 Construction C Ø8 max. 2 M4 x 20 Thermal diagrams Max. load current 30 A Max.
DIN rail or panel mount with integrated heat sink Solid-state relay HD Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HD D2825K Yes – DC AC HD D6035K Yes – DC AC HD D6050K Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Thyristor value Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
Standard panel mount package Solid-state relay HD Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HD D6075K Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Thyristor value Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I2t for fusing (10 ms) Thermal resistance to base 24 ...
ESG 8.
Current monitoring module for HD series solid state relays Current monitoring HD D0340I • Control voltage range: 4 ... 30 VDC • Load current range: 2 A ...
Current monitoring module for HD series solid state relays Current monitoring HD D0340I Wiring diagram Functional digaram ESG 8.
Current monitoring module for HD series solid state relays Current monitoring HD D0340I Teaching mode diagram ESG 8.
Current monitoring module for HD series solid state relays Current monitoring HD D0340I Setting sequence Brief activation (< 2 s) of the Teach key or the external digital Teach input makes it possible to test the system (relay and load), in which case the control input of the solid state relay is activated. Longer activation (> 3 s) of the Teach key or the external digital Teach input makes it possible to record and store the load current of the „Iteach“ load (teach mode).
Current monitoring module for HD series solid state relays Current monitoring HD D0340I Example of wiring with several modules The diagnostic outputs of several modules (max. 5) can be connected in parallel to one input of a controller. In the event of a fault, the controller detects a fault and the „Fault“ LED makes it possible to identify the fault type and fault location on the modules.
Current monitoring module for solid state relays type HD Current monitoring module HD D0340I Technical data of power supply (at 25°C) Voltage range Control current Polarity reversal protection Surge voltage protection HD D0340I 8 ... 30 VDC <20 mA yes Varistor Technical data in general (at 25°C) Switch-on time @ 50Hz (t on) Switch-off time @ 50Hz (toff) Diameter of cable entry for current converter Index of protection CEI520 Vibration (10 … 55Hz acc. to IEC 60068-2-6) Schock (1/2 sinusoidal/11 ms acc.
Standard panel mount package, 3-phases Solid-state relay HL • Control voltage range: 8,5 ... 30 VDC, 90 ... 240 VAC/DC • Load voltage range: 24 ... 520 VAC • Load current range: 3 x 50 A Dimensions 76 58,4 Construction V 40 91 4,4 23 M3.5 Thermial diagrams Max.
Standard panel mount package, 3-phases Solid-state relay HL Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HL D5250 Yes – DC AC HL A5250 Yes – AC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
3-phases with integrated heat sink Solid-state relay HL • Control voltage range: 10 ... 30 VDC • Load voltage range: 24 ...
3-phases with with integrated heat sink Solid-state relay HL Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HL D5222K Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max. I 2t for fusing (10 ms) Thermal resistance to base 24 ... 520 VAC 10 ..
Standard panel mount package, 3-phases reversing contactor Solid-state relay HL • Control voltage range: 12 ... 30 VDC • Load voltage range: 24 ... 520 VAC • Load current range: 3 x 8,5 A Dimensions 76 58,4 40 M5 56,5 91 4,4 23 M3.5 Thermal diagrams Max. load current 8,5 A 30 30 1,2 K/W = WF121100 25 25 Power loss (W) Full on state 20 20 15 15 10 10 5 5 without heatsink 0 0 0 2 4 6 8 Load current A(rms) 10 12 0 10 20 30 Heat sinks see on pages 32, 33 and 34 ESG 8.
Standard panel mount package, 3-phases reversing contactor Solid-state relay HL Technical specifications Zero switching Instantaneous switching-on Control circuit Load circuit HL D5208R Yes – DC AC Load circuit Voltage range Operating frequency range Transient overvoltage Load current range Max. surge current (10 ms) Max. off-state leakage current (rated voltage) Min. off-state du/dt Max. on-state voltage drop Max. turn-on time Max. turn-off time Max.
Accessories Heat sink for 1- and 3-phases solid-state relays A 62 48 10 124 30 35 14 75 72 It is essential to use heat conduction foil or heat conductive paste between the solidstate relay and the heat sink. Heat conduction foil is already applied on or supplied with all Selectron semiconductor relays! B 7,5 22,5 73,5 66 70 80 M4 x 0.7 L 10 min 70 47,6 12,7 M5 M4 86 - 90 98 Description Heat sink 0,7 °C/W Heat sink 3,0 °C/W (Order data see chapter 1) ESG 8.
Accessories Heat sink for 1- and 3-phases solid-state relays C M4 x 0.7 L 10 min 7,5 45 73,5 66 71,5 80 47,6 12,7 M5 M4 86 - 90 98 D It is essential to use heat conduction foil or heat conductive paste between the solidstate relay and the heat sink.
Accessories Heat sink for 1-phase solid-state relays printed circuit board mount A B Dimension A: Dimension B: height x width x length 45 x 30 x 100 mm height x width x length 45 x 30 x 150 mm Mounting examples C Thermal heatsinks with clip mounting system Heatsinks references: HKT 3.0: L = 100 mm about 4 K/W (1 relay) without ventilation (3,6 K/W with 4 relays) HKT 4.
Accessories Ventilator for 1- and 3-phases solid-state relays Heat sink with fan for all screw-on relays Type HK 0,3 LB 230 Operating voltage 230 Vac Power consumption 9W Heat dissipation with HRK 0,5 0,3 °C/W Weight without heat sink 1’770 g Fasteningscrews for 3-phases relays are included in delivery Article number 42310305 (Order data see chapter 1) one phase or three phases relays mounting 120 Thermostat open if >85° C 110 115 145 126 1 or 2 three phase relay 90 110 100 100 one phase rela
Accessories DIN-mounting DIN-mounting DB 2 for construction HRS (Order data see chapter 1) ESG 8.42 Weight 60 g Article no.
Application notes Contact free switching in all domains Solid state relays from Selectron Systems AG are particularly suitable for ranges where high currents have to be switched fast, such as e.g. in regard of the temperature control on heatings or where there are strong vibrations (no moving mechanical parts), or when there are heavy environmental conditions such as high humidity, extreme temperatures etc.
Technical safety advice This manual contains the information necessary for the correct utilisation of the products described therein.
Application notes (SSR) Definition A SSR (solid state relay) is able to perform many tasks that an EMR (electromechanical relay) can perform. The SSR differs in that it has no moving mechanical parts within it. It is essentially an electronic device that relies on the electrical, magnetic and optical properties of semiconductors, and electrical components to achieve its Isolation and relay switching function.
For a better understanding of SSRs, an SSR Operational description is included. It has to be said that an in-depth understanding of the internal circuitry of an SSR and how it functions are not in themselves a prerequisite to the use of SSR in many applications. Most SSRs in the higher current ranges are offered with either ac or dc control options. Indeed many have some form of current limiting at their input in order to provide a practical operating voltage range. dc inputs Figs.
output pair is capable of operating at much higher frequencies. Wowever, because of circuit time constraints in the drive circuitry, other SSR parameters become the limiting factors (e.g. the zero switching window may be extended and/or turn-delayed each half cycle with eventual lock.on or lockout). Zero switching Zero voltage turn-on (or zero crossing), as illustrated in Fig 4, is used in some ac SSRs to reduce electromagnetic interference and high inrush currents.
Selecting the ideal SSR In a bid to specify the exact SSR for an application, it is important to consider the: • input drive requirement • output current • load or output current • the isolation and installation requirements The activating signal may be derived from mechanical contacts or solid state devices such as those shown in figure 6 The minimum supply voltage through these contacts may be equal to the SSR turn-on voltage (3 volts dc typical), whereas the positively or negatively referenced transisto
TTL drive methods A standard TTL gate can drive most SSRs with ist 16 mA sink capability. However, very few SSRs can be driven reliably with the gates' available source current of only 400 μA. Also, the SSR minimum voltage threshold requirements are not met in the source mode (i.e. gate output in the positive leg of the SSR). The relationship of the TTL gate to an SSR is illustrated schematically in Fig. 6.
IC and other drive sources Most CMOS and NMOS logic families will not directly interface with SSRs, except for a few specially designed types. However, a CMOS buffered gate can reliably drive an SSR that has low input power requirements (i.e. >1500 ohms at 5 volts) and is also driven in the sink mode the same as TTL. Fig. 7 shows 1/6 of 4049 (inverting) or a 4050 (noninverting) CMOS hex buffer driving such an SSR with a common 5 volt supply.
Leakage from the drive source The off state leakage current in the driving semicoonductors shown in Figs. 6 to 8 is significant, just a few microamperes, which could not possibly turn on the SSRs. However, the off state (output leakage current of any packaged solid state driving device (e.g. temperature controller, etc.) should first be checked for compatibility with the SSR. One method is to multiply the maximum leakage current (amps) by the maximum input impedance (ohms) of the SSR.
(a) To determine the maximum allowable ambient temperature: Heat sink = 1°C/W, Load = 10 A (12 W), T Jmax. = 100 °C TJ - TA = P (RθJC + RθCS + RθSA) hence, TA = TJ - 28,8 TJ - TA = 12 (1,3 + 0,1 + 1,0) TA = 100 - 28,8 TJ - TA = 28,8 TA = 71,2 °C Regardless of whether the SSR is used on a heat sink or the case is cooled by other means, it is possible to confirm proper operating conditions by making a direct base plate temperature measure-ment when certain parameters are known.
TJ - TA = P (RθJC + RθJA) or TJ - TA = P (RθJA) where: (RθCA) = Thermal resistance, case to ambient, [°C/W] (RθJA) = Thermal resistance, junction to ambient, [°C/W] The equation can be used to calculate maximum load current and maximum ambient temperature as before. However, the resultant values are inclined to be less precise due to the many variable that affect the case to air relationship (i.e., positioning, mounting, stacking, air movement, etc).
Surge ratings and high inrush current loads After improper heat sinking, surge current is one of the more common causes of SSR failure. Overstress of this type can also seriously impair the life of the SSR. Therefore, in a new application it would be wise to carefully examine the surge characteristics of the load. There are very few completely surgeless SSR loads. Resistive loads, such as heating elements and incandescent lamps, can prove problematic.
At the instant turn-on, transformer current is essentially zero, with the highest peak usually occurring within a half cycle, depending on the line phase angle, load power factor, and magnetic state of the core. When the SSR is energized at the ideal phase angle, as dictated by power factor, a maximum back EMF is generated that will tend to counter the magnetising current, thereby reducing or eliminating the surge.
Suppressors When overvoltage transients occur, another form of suppression may be required beyond the capabilities of the snubber. One popular technique is to add a clamping device across the SSR terminals that will absorb the transient energy above a predetermined level. Devices, such as zeners and MOVs, will conduct only at the predetermined level and above, thereby sharing the transient with the load.
Diodes and Zeners The diode shown across the load in A of Fig. 12 is the most effective way of suppressing the possibly hundreds of volts of bak EMF that can be generated by the coil at turn-off. The disadvantages of this method are the SSR is not protected from other transient sources, and the dropout time of the load may be extended by several milliseconds. The general rule in the selection of protective diodes and zeners is that their peak nonrepetitive (pulse) current ratings (Fig.
SSR Applications Latching SSR with short-circuit protection (Fig. 14) Push-button control as in the previous example, but R2 is tailored to limit the load shorting current to SSR surge rating (for turn-off time), thus preserving SSR while the control signal is removed. Latching characteristic permits lock-out until the circuit is reset. The diagrams in this section are conceptual illustrations of just a few typical SSR applications.
Functional Three-phase switch for Three-wire system (Fig. 16) Two SSRs may be used to control a Y or a delta load in a three-wire system. A third SSR would be required in phase C if the centre of the Y load were grounded, as in a four-wire system. SSR voltage rating must be greater than line to line voltage for three-wire systems and line to ground voltage for four-wire systems (with neutral ground).
Three-phase motor reversal (Fig. 17) For ac SSRs can provide a reversing function for a three-phase motor, using the drive logic suggested. The half cycle time delay before enabling the drive, in either direction, prevents make before break which would result in a line to line short. Two opposing SSRs (nos. 1 and 4, or 2 and 3 ) could still mistrigger simultaneously due to dv/dt or high voltage transients; therefore, resistors R1 through R4 are inserted to limit the resultant surge current.
Reversing motor drive for dc Motors (Fig. 18) In this configuration, four dc SSRs are used for motor reversal from a single power supply. The time delay before enabling the drive in either direction must be greater than the SSR turn-off time to preclude the possibility of a hazardous make before break condition. Internal reverse diodes or zeners in the SSRs will suppress inductive transients across the low impedance of the power supply.
Paralleling SSRs (Fig. 19) SSRs with MOSFET outputs are self balancing and easily paralleled, whereas most others with bipolar or thyristor outputs require special attention. Ideally, the forward voltage drops should be matched to achieve thermal balance and lowest dissipation; alternatively, balancing resistors (Rx) are used to force current sharing as shown, For example, with 40 amps allowed through SSR1, SSR2 must carry 32 amps.
Transformer Tap switching (Fig. 20) If a momentary interruption in power is acceptable, a time delay on operate is suggested to prevent overlap and the resulting high current surge form a shorted winding. Two times Rx plus the winding resistance must be sufficcient to limit the surge current to the one cycle surge rating of the SSRs. As an additional precaution, the SSR blocking (breakdown) voltage should exceed the main winding voltage plus the highest tap voltage.
Testing the SSR (Fig. 21) Many of the tests required to verify SSR performance are inherently hazardous and caution should be exercised, using adequate safeguards for the personnel conducting such tests. Possibly the simplest of all field tests that can be made to determine proper function of an AC SSR is by means of a 3 volt battery, a light bulb, and a piece of insulated wire. This simple go/no-go test is illustrated by Fig. 21.
Glossary of terms Ambient temperature range. The surrounding air temperature limits, usually given for both operating and storage conditions. The maximum operating temperature may require close consideration by the thermal dictates of heat dissipation and the possible requirement of a heat sink. Anode - Connection of a thyrisor. High potential terminal on an SCR. Positive in respect to gate and cathode when conducting (blocking when negative). Base. The control terminal of a bipolar transistor. Bipolar.
Phase control. Turn-on of a nonzero switching SSR (each half cycle), at a phase angle determined by the control signal source. Power dissipation. The maximum average power dissipation [watts] resulting from the effective voltage drop (power loss) in the SSR output semiconductor. RMS Voltage (Root-Mean-Square). The value of alternating voltage (ac) that would produce the same power dissipation as continuous voltage (dc) in a resistive load. For a sine wave, RMS is 0,707 times the peak value.
