Protection Circuit - Panasonic AQ-G Manual

Cautions for Use of Solid State Relays
Thermal Design
SSRs used in high-reliability equipment require careful thermal
design. In particular, junction temperature control has a
significant effect on device function and life time. The rated load
current for PC board-mounting SSRs is defined as the maximum
current allowable at an ambient temperature of 40°C
(30°C 86°F) and under natural cooling. If the ambient
temperature exceeds the SSRs derating temperature point
[40°C 104°F (30°C 86°F)], load current derating in accordance
with the load current vs temperature diagram becomes
necessary.
If adjacent devices act as heat sources, the SSR should be
located more than 10 mm away from those devices.
SSRs with a 5 A rating or more must be used with the dedicated
heat sinks listed in Table 1 or equivalents. To ensure adequate
thermal conduction, apply thermal conductive compound (Ex.
Momentive Performance Materials Inc. YG6111 or TSK5303) to
the SSR's mounting surface.
For information on external heat sinks for our SSRs and their
mounting method, refer to "Data and Cautions for Use for
respective relay".

Protection Circuit

High-reliability SSR circuits require an adequate protection
circuit, as well as careful study of the characteristics and
maximum ratings of the device.
1. Over-Voltage Protection
The SSR load power supply requires adequate protection
against over-voltage errors from various causes. The methods of
over-voltage protection include the following:
1) Use devices with a guaranteed reverse surge withstand
voltage
(controlled avalanche devices, etc.)
2) Suppress transient spikes
Use a switching device in the secondary circuit of a transformer
or use a switch with a slow opening speed.
Choosing the rated voltage of the ZNR
(1) Peak supply voltage
(2) Supply voltage variation
(3) Degradation of ZNR characteristic (1 mA±10%)
(4) Tolerance of rated voltage (±10%)
For application to 100 V AC lines, choose a ZNR with the
following rated voltage:
(1) × (2) × (3) × (4) = (100 × M2) × 1.1 × 1.1 × 1.1 = 188 (V)
Example of ZNR (Panasonic)
Varistor voltage
Types
V1mA (V)
ERZV14D201 200 (185 to 225)
ERZV14D221 220 (198 to 242)
ERZV14D241 240 (216 to 264)
ERZV14D271 270 (247 to 303)
ERZV14D361 360 (324 to 396)
ERZV14D391 390 (351 to 429)
ERZV14D431 430 (387 to 473)
ERZV14D471 470 (423 to 517)
ERZV14D621 620 (558 to 682)
ERZV14D681 680 (612 to 748)
104°F
Max. allowable circuit Max. control
voltage voltage
ACrms (V) DC (V) V50A (V)
130 170 340
140 180 360
150 200 395
175 225 455
230 300 595
250 320 650
275 350 710
300 385 775
385 505 1,025
420 560 1,120
Table 1 Dedicated on-board heat sinks
Type
AQ10A2-ZT4/32VDC AQ-HS-5A
AQP-HS-SJ10A*
AQ-J (10A) AQP-HS-J10A
AQP-HS-SJ20A*
AQP-HS-SJ10A*
AQ-J (15A) AQP-HS-J10A
AQP-HS-SJ20A*
AQP-HS-SJ10A*
AQP-HS-J10A
AQ-J (25A)
AQP-HS-SJ20A*
AQP-HS-J25A
AQP-HS-J10A
AQ-A (15A)
AQP-HS-SJ20A*
AQP-HS-30/40A
AQ-A (25A) AQP-HS-J10A
AQP-HS-SJ20A*
AQP-HS-J10A
AQP-HS-SJ20A*
AQ-A (40A)
AQP-HS-30/40A
AQP-HS-J25A
AQP-HS-SJ20A*
AQ-A DC (10A)
AQP-HS-J25A
AQ-A DC (30A) AQP-HS-SJ20A*
*It is possible to mounting on the DIN rail
3) Use a surge absorption circuit
Use a CR surge absorber or varistor across the load power
supply or SSR.
Special care must be taken so power on/off surges or external
surges do not exceed the device's rated load voltage. If a surge
voltage exceeding the device's rated voltage is anticipated, use
a surge absorption device and circuit (e.g. a ZNR from
Panasonic Corporation).
D
0.8 dia.
3.0 max.
.031 dia.
.118 max.
W
Withstanding energy
Max. average
pulse electric
(10/1000μs) (2ms)
power
(W) (J) (J)
0.6 70 50
0.6 78 55
0.6 84 60
0.6 99 70
0.6 130 90
0.6 140 100
0.6 155 110
0.6 175 125
0.6 190 136
0.6 190 136
ー 10 ー
Heat sink Load current
10A
10A
15A
20A
25A
15A
25A
30A
40A
8A
10A
30A
T
H
D: 17.5 dia. max.
.689 dia. max.
T: 6.5 max.
.256 max.
20.0 min.
.787 min.
H: 20.5 max.
.807 max.
W: 7.5±1
.298±.039
L
(Unit: mm inch)
Withstanding surge current Electrostatic
capacitance
(8/20μs)
1time
(Reference)
2time
(A) (A) @1KHz (pF)
6,000 5,000
6,000 5,000
6,000 5,000
6,000 5,000
6,000 4,500
6,000 4,500
6,000 4,500
6,000 4,500
5,000 4,500
5,000 4,500
ASCTB400E 201806-T
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