# PCB relay, through-hole

A through-hole PCB relay: a closed case on the board with its pins at the maker's PCB layout. Pin 1 is at the origin. The pins are placed as the maker's bottom-view PCB layout draws them, seen from above (the layout turned over about its horizontal axis). The layout's rows run along +X, and its next row is towards +Y. The pins go down through the board. The Finder 34.51 flat pack lies on the board, its pins bent down at one long side.

## Omron

| Type | Contacts | Case (average) | Pins below the board | Pin section | PCB layout: columns from pin 1 | Rows apart | Pin 1 from the case end, side | Weight (sheet) |
|---|---|---|---|---|---|---|---|---|
| G2RL-2 | DPDT, power | 28.8 x 12.5 x 15.5 | 3.5 | 0.5 x 0.8 | 0, 15, 20, 25 | 7.5 | 2.3, 2.5 | approx. 12 g |
| G5V-1 | SPDT, signal | 12.3 x 7.3 x 9.9 | 3.5 | 0.5 x 0.3 | 0, 2.54, 10.16 | 5.08 | 1.07, 1.11 | approx. 2 g |
| G5V-2 | DPDT, signal | 20.3 x 9.9 x 11.4 | 3.5 | 0.5 x 0.3 | 0, 7.62, 12.7, 17.78 | 7.62 | 1.3, 1.2 | approx. 5 g |
| G6A | DPDT, signal | 20 x 9.9 x 8.2 | 3.16 | 0.6 x 0.3 | 0, 7.62, 12.7, 17.78 | 7.62 | 1.2, 1.2 | approx. 3.5 g |
| G6AK | DPDT, signal, double-winding latching | 20 x 9.9 x 8.2 | 3.16 | 0.6 x 0.3 | 0, 2.54, 7.62, 12.7, 17.78 | 7.62 | 1.2, 1.2 | approx. 3.5 g |

The case sizes are the data sheets' average values (their maximums are 0.2 to 0.3 larger). The distances from pin 1 to the case are the PCB layouts' bracketed reference values, and the case's far end takes what's left of its average size.

## Source

Omron data sheets, from Omron's own site (omronfs.omron.com/en_US/ecb/products/pdf/):

- *PCB Power Relay G2RL*, Cat. No. J117-E1-17 (`en-g2rl.pdf`): weight approx. 12 g (Ratings, page 2); Dimensions, page 6, G2RL-2(-HA, -PW1), G2RL-24, G2RL-2-ASI: 29 max. (28.8) x 12.7 max. (12.5) x 15.7 max. (15.5), terminals 3.5 long, 0.5 and 0.8; PCB mounting holes: eight, 20 from pin 1 to the third column, the columns 5 apart, the rows 7.5 apart, (2.3) and (2.5) to the case.
- *Low Signal Relay G5V-1*, Cat. No. K048-E1-07 (`en-g5v_1.pdf`): weight approx. 2 g; Dimensions, page 4: 12.5 max. (12.3) x 7.5 max. (7.3) x 10 max. (9.9), terminals 3.5, 0.5 and 0.3; six holes at 2.54, 7.62 (10.16 in all) and 5.08, (1.07) and (1.11) to the case.
- *Low Signal Relay G5V-2*, Cat. No. K046-E1-06 (`en-g5v_2.pdf`): weight approx. 5 g; Dimensions, page 4: 20.5 max. (20.3) x 10.1 max. (9.9) x 11.5 max. (11.4), terminals 3.5, 0.5 and 0.3; eight holes at 7.62, 5.08, 5.08 and 7.62 apart, (1.3) and (1.2) to the case.
- *Low Signal Relay G6A*, Cat. No. K020-E1-15 (`en-g6a.pdf`): weight approx. 3.5 g; Dimensions, page 8: G6A-274P and G6AU-274P, 20.2 max. (20) x 10.1 max. (9.9) x 8.4 max. (8.2), terminals 3.16 long, 0.6 and 0.3; eight holes at 7.62, 5.08, 5.08 and 7.62 apart, (1.2) to the case; G6AK-274P, ten holes, with a column 2.54 from pin 1.

The data sheets name no materials.

**Proportions, for looks and mass.** The data sheets don't dimension the inside. The case is a cover 0.5 thick over a base plate 0.5 thick. The coil, core and contacts inside are one copper block filling 0.27 of the space inside the case and standing on the base. That share is the same for every type.

Mass, with `pa6` at 1.15 and `copper` at 8.96 g/cm³:

| Type | Model | Data sheet |
|---|---|---|
| G2RL-2 | 12.4 g | approx. 12 g |
| G5V-1 | 1.85 g | approx. 2 g |
| G5V-2 | 4.94 g | approx. 5 g |
| G6A, G6AK | 3.45 g | approx. 3.5 g |

The case is black (`pa6`), and the pins are tin-plated copper.

`Relay_DPDT_Omron_G6A` and `G6AK` in the old catalogue were measured (2026-11-06): a case 20 x 9.9 x 8.2 with pins 3.16 below, pin 1 1.14 from the case's end and 1.21 from its side, against the sheet's (1.2) and (1.2). That's within 0.07, and the pins are at the same places. The catalogue's G2RL, G5V-1 and G5V-2 entries have no model. They name the part, and the sheets above give it.

## Finder

Pin 1 is coil terminal A1. The sizes are the sheets' nominal values (they give no maximums).

| Type | Contacts | Case | Pins below the board | Pin section (along the case x across it) | PCB layout from A1 | Pin 1 from the case end, side |
|---|---|---|---|---|---|---|
| 30.22 | DPDT, 2 A | 20.2 x 10 x 10.9 | 3.2 | coil 0.4 x 0.4, contacts 0.6 x 0.4 | 11, 12, 14 at 7.62, 12.7, 17.78; A2 row 7.62 across | 1.12, 1.19 |
| 32.21-4000 | SPDT, 6 A | 20.2 x 10.1 x 10.7 | 3.5 | coil 0.4 x 0.4, contacts 0.8 x 0.3 | 11, 14 at 10.16, 17.78; A2 and 12 7.62 across | 1.32, 1.24 |
| 32.21-4300 | SPST-NO, 6 A | as 32.21-4000, without 12 | 3.5 | as above | as above | 1.32, 1.24 |
| 34.51 | SPDT, 6 A, 5 mm wide | 28 x 5 x 15 | 3.5 | coil 0.5 x 0.5, contacts 1 x 0.4 | one row: A2 at -3.75, 12, 11, 14 at 11.25, 16.25, 21.25 | 4.85, 3.7 |
| 34.51-flat | as 34.51, flat pack (34.51.7xxx.x019) | 28 x 15 lying, 5 high | 2.5 | as 34.51 | as 34.51, at the case's long side | 4.85, -0.4 (the case starts 0.4 past the pin row) |
| 36.11 | SPDT, 10 A (36.11-4011) | 18.8 x 15.2 x 15.5 | 3.5 | coil 0.5 x 0.5, 11 0.3 x 1.2, contacts 1 x 0.5 | A2 12 across; 11 at -2, 6 across; 14, 12 at 12.2 | 3.2, 1.6 |
| 40.31 | SPDT, 12 A, 3.5 mm pitch | 29 x 12.4 x 25.1 | 5.2 | 0.4 x 1 | 12, 14 at 16.5, 23.5; A2 7.5 across, 11 at 20 in its row | 2.5, 2.45 |
| 40.51 | SPDT, 12 A, 5 mm pitch | 29 x 12.4 x 25.1 | 5.2 | 0.4 x 1 | 12, 14 at 15, 25; 11 at 20 in A2's row | 2.5, 2.45 |
| 40.52 | DPDT, 8 A | 29 x 12.4 x 25.1 | 5.2 | 0.4 x 1 | 15, 20, 25 in both rows, 7.5 apart | 2.5, 2.45 |
| 40.61 | SPDT, 16 A | 29 x 12.4 x 25.1 | 5.2 | 0.4 x 1 | as 40.52 | 2.5, 2.45 |

`40.31-3.5`, `40.51-3.5` and `40.61-3.5` are the same relays with the 3.5 mm pins of the PCB-only versions (ordering code digit C = 2); the others have the 5.2 mm pins for PCB or sockets (40.52 comes only with those).

### Source

Finder series sheets, from Finder's own site (cdn.findernet.com/app/uploads/), with the edition printed on each page:

- *30 Series, Subminiature DIL relays 2 A*, edition II-2026 (`S30EN.pdf`): copper side view, page 3: A1, 11, 12, 14 at 7.62, 5.08 and 5.08 apart, rows 7.62 apart, 14 1.3 from the case end, case 20.2 x 10; outline drawing, page 5: 20.2 x 10 x 10.9, pins 3.2 long, 0.4 (coil) and 0.6 (contacts) wide, 0.4 thick.
- *32 Series, Subminiature PCB relays 6 A*, edition XII-2025 (`S32EN.pdf`): copper side views of 32.21-4000 and -4300, page 3: 10.16 and 7.62, rows 7.62 apart, 14 1.1 from the case end, case 20.2 x 10.1; outline drawing, page 5: 20.2 x 10.1 x 10.7, pins 3.5, 0.4 x 0.4 (coil) and 0.8 x 0.3 (contacts).
- *34 Series, Ultra-Slim PCB relays*, edition II-2026 (`S34EN.pdf`): copper side view of 34.51, page 3: 3.75, 11.25, 5 and 5, the row 1.3 from the case side, 14 1.9 from the end, case 28 x 5; flat pack version, page 6: case 28 x 15, the pin row 15.4 from the far side, the pins' ends 7.5 from the case's far face; outline drawing, page 9: 28 x 5 x 15, pins 3.5, 0.5 x 0.5 and 1 x 0.4.
- *36 Series, Miniature PCB relays 10 A*, edition II-2026 (`S36EN.pdf`): copper side view of 36.11-4011, page 3: 2, 12.2 and 3.4 along, 6 and 6 across, case 18.8 x 15.2; outline drawing, page 5: 18.8 x 15.2 x 15.5, pins 3.5, 0.3 x 1.2 (11), 0.5 (coil) and 1 (contacts) along the case.
- *40 Series, PCB/Plug-in relays 8 - 10 - 12 - 16 A*, edition VIII-2026 (`S40EN.pdf`): copper side views, page 3: 2.5 and 20, 3.5 + 3.5 (40.31) or 5 + 5 (40.51, 40.52, 40.61), rows 7.5 apart, case 29 x 12.4; pin lengths 3.5 (PCB only) and 5.2 (PCB or socket), pages 3 and 5; outline drawing, page 10: 29 x 12.4 x 25.1, pins 0.4 x 1.

The sheets name no materials and give no weight.

**Proportions.** The sheets dimension the rows and the case width but not the gap between them: the rows are centred across the case. The 36.11's coil and contact pins are taken as 0.5 thick across the case, as drawn (the sheet gives only their width along it). The small standoffs under the 32.21 (0.4) and 34.51 (0.3) cases aren't modelled: the case stands on the board. The flat pack's pins bend 1.3 above the board, the standing version's 1.3 from the case side. The inside is the Omron proportions: a 0.5 cover and base, and a copper block filling 0.27 of the inside.

Mass (no weight in the sheets to compare with): 30.22 4.75 g, 32.21 4.69 g, 34.51 4.39 g, 36.11 9.8 g, 40 series 20.2 to 20.3 g.

The 30, 32 and 36 cases are white, the 40 series' blue and the 34.51 black, as in Finder's pictures.

### The old catalogue's models

Measured 2026-11-06 against the sheets. The pin positions are the same in every model. The cases and pins differ:

| Model | Case (model / sheet) | Pin 1 from the case end (model / sheet) | Pins below (model / sheet) | Pin sections (model / sheet) |
|---|---|---|---|---|
| `Relay_DPDT_Finder_30.22` | 20.3 x 10.1 x 11.4 / 20.2 x 10 x 10.9 | 1.26 / 1.12 | 3.5 / 3.2 | all 0.7 x 0.4 / coil 0.4 x 0.4, contacts 0.6 x 0.4 |
| `Relay_SPDT_Finder_32.21-x000`, `Relay_SPST_Finder_32.21-x300` | 20 x 10 x 10.7 / 20.2 x 10.1 x 10.7 | 1.4 / 1.32 | 3.0 / 3.5 | contacts 0.6 x 0.4 / 0.8 x 0.3 |
| `Relay_SPDT_Finder_34.51_Vertical` | 28 x 5 x 15, the same | 4.85, the same | 3.5, the same | the same |
| `Relay_SPDT_Finder_34.51_Horizontal` | 28 x 15.85 (with the pins) x 5 / 28 x 15.4 x 5 | 4.85, the same | 3.0 / 2.5 | the same |
| `Relay_SPDT_Finder_36.11` | 19 x 15.2 x 15.5 / 18.8 x 15.2 x 15.5 (turned 90 degrees) | 3.4 / 3.2 | 3.5, the same | contacts 1 x 0.4 / 1 x 0.5 (thickness not given) |
| `Relay_SPDT_Finder_40.31`, `40.51`, `Relay_DPDT_Finder_40.52` | 29 x 12.4 x 25 / 29 x 12.4 x 25.1 | 3.0 / 2.5 | 5.3 / 5.2 | the same |

The catalogue's x000 and x300 stand for 32.21-4000 and -4300, the only 32.21 types in the sheet. Its `Finder_40.11` and `40.41` aren't in the 40 series sheet (edition VIII-2026), so they're left out.

## Schrack (TE Connectivity)

Pin 1 is coil terminal A1. The kinds are the product codes' first letters and digits (RT114024 is an `RT11`, RT424024 an `RT42`, RY211024 an `RY21`).

| Type | Contacts | Case | Pins below the board | PCB layout from A1 (A2's row 7.5 across, RY II 7.62) | Pin 1 from the case end, side | Weight (sheet) | Model |
|---|---|---|---|---|---|---|---|
| RT11 | RT1 SPDT 12 A, 3.5 mm pinning | 29.0 x 12.7 x 15.7 | 3.6 | 12, 14 at 16.8, 23.8; 11 at 20.3 in A2's row | 2.35, 2.6 | 14 g | 12.85 g |
| RT13 | RT1 SPST-NO 12 A, 3.5 mm | as RT11 | 3.6 | 14 at 23.8; 11 at 20.3 in A2's row | 2.35, 2.6 | 14 g | 12.85 g |
| RT21 | RT1 SPDT 12 A, 5 mm pinning | as RT11 | 3.6 | 12, 14 at 15.26, 25.34; 11 at 20.3 in A2's row | 2.35, 2.6 | 14 g | 12.85 g |
| RT23 | RT1 SPST-NO 12 A, 5 mm | as RT11 | 3.6 | 14 at 25.34; 11 at 20.3 in A2's row | 2.35, 2.6 | 14 g | 12.85 g |
| RT31 | RT1 SPDT 16 A, 5 mm | as RT11 | 3.6 | 12, 11, 14 at 15.26, 20.3, 25.34 in both rows | 2.35, 2.6 | 14 g | 12.9 g |
| RT33 | RT1 SPST-NO 16 A, 5 mm | as RT11 | 3.6 | 11, 14 at 20.3, 25.34 in both rows | 2.35, 2.6 | 14 g | 12.87 g |
| RT42 | RT2 DPDT 8 A | as RT11 | 3.6 | 12, 11, 14 and 22, 21, 24 at 15.26, 20.3, 25.34 | 2.35, 2.6 | 13 g | 12.9 g |
| RT44 | RT2 DPST-NO 8 A | as RT11 | 3.6 | 11, 14 and 21, 24 at 20.3, 25.34 | 2.35, 2.6 | 13 g | 12.87 g |
| RY21 | RY II SPDT 8 A, 3.2 mm pinning | 28.5 x 10.1 x 12.3 | 3.2 | 22.1; 18.9 and 25.3 in A2's row | 1.9, 1.24 | 8 g | 7.72 g |
| RY53 | RY II SPST-NO 8 A, 5 mm pinning | as RY21 | 3.2 | 18.9; 23.94 in A2's row | 3.25, 1.24 | 8 g | 7.71 g |
| RY5-NC | RY II SPST-NC 8 A, 5 mm | as RY21 | 3.2 | as RY53 | 3.25, 1.24 | 8 g | 7.71 g |

### Source

Schrack data sheets by TE Connectivity, read from Chip and Dip's copies (static.chipdip.ru) and Conrad's (asset.conrad.com):

- *Power PCB Relay RT1*, 01-2020, Rev. 0120 (static.chipdip.ru/lib/681/DOC011681392.pdf): PCB layout / terminal assignment, bottom view on solder pins, page 2: rows 7.5 apart, 20.3 from A1 to 11, 22.65 from the case end to 11, 3.5 (3.5 mm pinning) or 5.04 (5 mm) either side of 11, the 16 A layout with 12, 11 and 14 in both rows; weight 14 g, page 2; dimensions, THT version, page 3: 29.0 x 12.7 x 15.7, pins 3.6; the product code, page 3.
- *Power PCB Relay RT2 DC and AC (for Asia/Pacific markets)*, 11-2020, Rev. 1120 (static.chipdip.ru/lib/558/DOC013558502.pdf, a copy of the maker's sheet as downloaded from a distributor): page 2: dimensions 29.0 x 12.7 x 15.7, pins 3.6; PCB layout 7.5, 20.3, 22.65 and 5.04; weight 13 g; product code, page 3.
- *Printrelais RY II & RY II reflow-loetfaehig*, Datenblatt Rev. HC1, Ausgabe 2008/03 (Conrad's copy for item 504431, RY531005): page 2: dimensions 28.5 x 10.1 x 12.3, pins 3.2; Printbild (bottom view): 1.9, 18.9 and 3.2 (3.2 mm pinning), 3.25, 18.9 and 5.04 (5 mm, for both the make and the break contact); weight 8 g; Typenschluessel, page 3.

**Proportions.** The rows are centred across the case. The sheets don't dimension the pins: they are 0.55 along the case and 1.0 (RT1, RT2) or 0.8 (RY II) across it, scaled from the outline drawings (the outline's line centres, against its 29.0 or 28.5 and the 18.9 between pins). The RY II's rows are three steps of the sheet's 2.5 to 2.54 grid: 7.62 here. The inside is the Omron proportions. The RT1 comes out 8 % under its 14 g, the RT2 and RY II within 4 %.

The RT1 is red and the RT2 and RY II light grey and white, as in the sheets' pictures.

### The old catalogue's models

Measured 2026-11-06 (`Relay_SPDT_Schrack-RT1-FormC_RM5mm`, `-RT1-FormA`, `-RT1-16A-FormA`, `Relay_DPDT_Schrack-RT2-FormC`, `Relay_DPST_Schrack-RT2-FormA`, `Relay_1-Form-C_Schrack-RYII_RM3.2mm`, `-Form-A_` and `-Form-B_Schrack-RYII_RM5mm`). The pins are at the sheets' places and the cases are the sheets' sizes and places. Two things differ: the models' pins reach 5.3 below the board against the sheets' 3.6 (RT1, RT2) and 3.2 (RY II), and they are 0.4 x 1.0, where the drawings scale to 0.55 x 1.0 and 0.55 x 0.8.

The catalogue's `Relay_DPDT_Schrack-RT2-FormC-Dual-Coil_RM5mm` waits for a sheet with the dual-coil RT2.

## Tianbo HJR-4102

Pin 1 is coil terminal 1, as the sheet numbers it. `HJR-4102` is form C (ordering code ...-S-Z), `HJR-4102-A` form A (...-H), without pin 7.

| Type | Contacts | Case | Pins below the board | Pin section (along the case x across it) | PCB layout from pin 1 | Pin 1 from the case end, side | Weight (sheet) | Model |
|---|---|---|---|---|---|---|---|---|
| HJR-4102 | SPDT | 15.7 x 10.4 x 11.7 | 3.4 | coil 0.3 x 0.3; 5 and 8 0.45 x 0.3; 6 and 7 0.4 x 0.3 | 5, 6 at 10.16, 12.7; 12, 8, 7 in the row 7.62 across | 1.5, 1.39 | approx. 3.5 g | 3.43 g |
| HJR-4102-A | SPST-NO | as HJR-4102 | 3.4 | as above | as above, without 7 | 1.5, 1.39 | approx. 3.5 g | 3.43 g |

### Source

Ningbo Tianbo (TBO), data sheet *HJR4102* (通信继电器), read from Chip and Dip's copy (static.chipdip.ru/lib/163/DOC045163777.pdf; the PDF is dated 2019-04 and has no revision printed): ordering code and weight (approx. 3.5 g), page 1; overall and mounting dimensions, page 3: 15.7 x 10.4 x 11.7, pins 3.4; pins 0.3 thick, 0.3 (coil), 2-0.45 and 2-0.4 wide; six holes, 10.16 and 2.54 along, 7.62 across; wiring diagrams of form C and form A.

An older copy of the same sheet (static.chipdip.ru/lib/858/DOC029858842.pdf, document T810S-T002C) gives the case as 15.7 max. x 10.4 ±0.3 x 11.7 max., the pins 3.4 ±0.3, and the pins at 10.16 0.7 wide, not 0.45. The later sheet's values are used.

**Proportions.** The sheet doesn't place the pins in the case: the pattern is centred in it, 1.5 from each end (the side view draws it about 1.5 to 1.8 from the ends) and 1.39 from each side. The inside is the Omron proportions with a smaller block: it fills 0.22 of the inside, so that the mass comes out at the sheet's 3.5 g.

The case is black, as in the sheet's picture.

The old catalogue's `Relay_SPDT_HJR-4102`, measured 2026-11-06: the case 15.7 x 10.4 x 11.4 against the sheet's 11.7, pins 3.6 below against 3.4, all pins 0.3 x 0.3, pin 1 1.25 from the case end. Its 5 and 8 are at 9.86 from pin 1 and its 6 and 7 at 12.4, where the sheet puts them at 10.16 and 12.7: the model is wrong there, and the sheet's layout is used.

## Hongfa HF115F, 2 pole

Pin 1 is a coil terminal. The 2 pole, 8 A, 5 mm pinning versions (HF115F/xxx-2xx-x-4xx): `HF115F-2Z-4` 2 form C, `HF115F-2H-4` 2 form A, `HF115F-2D-4` 2 form B.

| Type | Contacts | Case | Pins below the board | Pin section (along the case x across it) | PCB layout from pin 1 | Pin 1 from the case end, side | Weight (sheet) | Model |
|---|---|---|---|---|---|---|---|---|
| HF115F-2Z-4 | DPDT, 8 A | 29 x 12.7 x 15.7 | 3.6 | coil 0.5 x 0.5, contacts 0.5 x 0.8 | 15.12, 20.16, 25.2 in both rows, 7.56 apart | 2.6, 2.57 | approx. 13.5 g | 12.86 g |
| HF115F-2H-4 | DPST-NO, 8 A | as 2Z | 3.6 | as above | 20.16, 25.2 in both rows | 2.6, 2.57 | approx. 13.5 g | 12.83 g |
| HF115F-2D-4 | DPST-NC, 8 A | as 2Z | 3.6 | as above | 15.12, 20.16 in both rows | 2.6, 2.57 | approx. 13.5 g | 12.83 g |

### Source

Hongfa data sheet *HF115F Miniature high power relay*, 2025 Rev. 1.00, from Hongfa's own site (source.hongfa.com/Uploads/Product/PDF/HF115F_en.pdf), pages numbered 219 to 222: unit weight approx. 13.5 g, page 219; outline dimensions, 5 mm pinning, page 221: 29 ±0.3 x 12.7 ±0.3 x 15.7 ±0.3, pins 3.6 ±0.5, terminals 0.5 x 0.5 and 0.5 x 0.8 (3 terminals); PCB layout (bottom view), 5 mm pinning, 2 pole, 8 A, page 222: 2.6 from the case end to the coil pins, 20.16 to the middle contacts, 5.04 either side, rows 7.56 apart, for 2 form A, B and C.

**Proportions.** The rows are centred across the case. The case's 0.3 standoffs aren't modelled: it stands on the board. The inside is the Omron proportions; the model is 5 % under the sheet's weight.

The case is black, as in the sheet's picture.

The old catalogue's `Relay_DPDT_Hongfa_HF115F-2Z-x4`, measured 2026-11-06: the case 29 x 12.7 and pin sections as the sheet's, 15.8 high (with standoffs) against 15.7, pins 3.4 below against 3.6, pin 1 2.54 from the case end and 2.54 from its side against 2.6 and 2.57. Its first contact column is at 15.2 against the sheet's 15.12 (20.16 less 5.04), 0.08 off: the sheet's layout is used.

## Sanyou SRD

Pin 1 is the common contact (the sheet numbers no pins). The sheet's bottom view, turned over and then half a turn, so that the common is at the case's -X end: the coil pins 2.0 on, 6 either side of the common's line, and the contacts 12.2 further on, 6 either side. `SRD-1C` is form C (the sheet's 1c), `SRD-1A` form A (1a: the contact on the -Y side), `SRD-1B` form B (1b: on the +Y side). The SRD-DM, SRD-D and SRD-DB ratings share the case.

| Type | Contacts | Case | Pins below the board | Pin section (along the case x across it) | Pin 1 from the case end, side | Weight (sheet) | Model |
|---|---|---|---|---|---|---|---|
| SRD-1C | SPDT | 19.6 x 15.4 x 15.5 | 3.5 | common 0.3 x 1; coil 0.55 x 0.55; contacts 1 x 0.4 | 1.3, 7.7 | approx. 8.5 g | 8.62 g |
| SRD-1A | SPST-NO | as SRD-1C | 3.5 | as above | 1.3, 7.7 | approx. 8.5 g | 8.61 g |
| SRD-1B | SPST-NC | as SRD-1C | 3.5 | as above | 1.3, 7.7 | approx. 8.5 g | 8.61 g |

### Source

Sanyou Relays, data sheet *SRD-Series Miniature Power Relay*, version V3.2, read from LCSC's copy (atta.szlcsc.com/upload/public/pdf/source/231023/SRD.pdf-ba91e5635ca2ace5c4c74973894313b7.pdf): unit weight approx. 8.5 g, page 1; outline dimensions, page 3: 19.6 x 15.4 x 15.5, pins 3.5; bottom view: 4.1, 12.2, 2.0 and 1.3 along the case, rows 6 and 6 from the centre line, 1.7 from the side, pins 1 wide and 2-0.4 thick (contacts), 2-□0.55 (coil), 0.3 and 1 (common); PCB layouts 1c, 1b and 1a (bottom view), page 3.

**Proportions.** The inside is the Omron proportions with a smaller block: it fills 0.22 of the inside, so that the mass comes out at the sheet's 8.5 g.

The case is black, as in the sheet's picture.

The old catalogue's `Relay_SPDT_SANYOU_SRD_Series_Form_C`, `Relay_SPST_SANYOU_SRD_Series_Form_A` and `_Form_B`, measured 2026-11-06: the pins at the sheet's places and the case at its size and place, turned the same way, with form A's contact on the -Y side and form B's on the +Y side. They differ in the case's height (15.6 against 15.5), the pins below the board (3.4 against 3.5), the coil pins (0.5 square against 0.55) and the contact pins (1 x 0.3 against 1 x 0.4).

## The family's other relays

Panasonic, Fujitsu, Kemet, COTO, CUI, Standex-Meder, HsinDa and Omron G6H, G6K, G6S, G6E, G5LE and G5NB aren't here yet; see `COVERAGE.md`.