Omron H3CR-A8 8-Pin Multi-Mode Solid-State Timer

H3CR-A8: 8-pin multi-mode timer in a 48 x 48 mm case

The Omron H3CR-A8 is the 8-pin member of the H3CR-A multifunctional solid-state timer line. It fits a standard DIN 48 x 48 mm cut-out, runs from a wide AC/DC supply band and drives a DPDT relay output, so one stocked unit covers a large number of control panels. Seven Star LLC supplies the H3CR-A8 in Oman and the GCC as an independent supplier in Muscat, and this page explains what the part number means and what to check before you order.

• H3CR is the series: DIN 48 x 48 mm panel timers with front time-range selectors.
• A marks the multifunctional timer type, where the operating mode is chosen on the front of the unit.
• 8 means an 8-pin plug-in base. The 11-pin form drops the 8 and adds external start, reset and gate inputs.
• No letter after the 8 means a DPDT relay output; S would be a transistor output and E would add an instantaneous contact.
• The supply voltage is appended when ordering, for example 100-240AC/100-125DC or 24-48AC/12-48DC. A -301 suffix selects the double time scale, 0.1 s to 600 h.

Because the H3CR-A8 has no external signal inputs, every cycle begins when power is applied. That makes it the simple, low-wiring choice for delayed starts, interval pulses and flashers where the supply itself is the trigger.

H3CR-A8 technical specifications

All values above come from the Omron H3CR datasheet. Note that the 24 to 48 VAC / 12 to 48 VDC versions draw an inrush current, so take care if the timer is switched by a non-contact sensor output; the datasheet refers to low-inrush variants that must be requested separately.

How H3CR-A8 handles timing

Inside the H3CR-A8 a one-chip microcomputer counts a clock against the time selected with the unit and full-scale selectors. When the count reaches the set value the output relay changes state, and the front LEDs show whether the timer is counting or the output is on.

Five operating modes are available on the 8-pin model, and all of them start when power is applied. ON-delay (A) energises the output after the set time. The two flicker modes (B and B2) alternate on and off at equal intervals, starting with the output off or on respectively. Interval (E) turns the output on at power-up and drops it after the set time, and one-shot (J) gives a single fixed pulse from power-up. Cutting power for at least 0.1 s resets the timer.

The time unit and full-scale knobs combine to give 24 ranges on standard 0.05 s to 300 h models. Turning the set value below zero until the stop makes the output act instantly, which is a quick way to check wiring and sequence without waiting for a long time range to run out.

Sockets, accessories and related timers for H3CR-A8

The H3CR-A8 shares the same 48 x 48 mm body and accessories as the rest of the H3CR-A, F, G and H families, so panels designed for an 11-pin timer can often be reworked to 8-pin with a different socket. If you need the extra inputs of H3CR-A, the voltage input of H3CR-AP, or an instantaneous contact as on H3CR-A8E, those are separate models. The sockets below are the ones the datasheet lists for 8-pin timers.

Accessories listed for the family include the Y92F-30, Y92F-73 and Y92F-74 flush-mounting adapters, the Y92A-48B protective cover, Y92H-7 and Y92H-8 hold-down clips, Y92S-27 and Y92S-28 setting rings, Y92P-48GL and Y92P-48GB panel covers, and the Y92A-48G terminal cover for back-connecting screw sockets. The protective cover and flush adapters cannot be combined with the panel cover, so settle the front-panel arrangement before ordering.

Selection and ordering checklist for H3CR-A8

Use this list before you send an enquiry for H3CR-A8. Omron orders timers by model plus supply voltage, so the voltage is part of the order and cannot be added later.

• Confirm that power-supply start is acceptable. If the cycle must be started by a signal while power stays on, you need the 11-pin H3CR-A or H3CR-AP instead.
• Choose the supply band: 100 to 240 VAC / 100 to 125 VDC, or 24 to 48 VAC / 12 to 48 VDC.
• Decide whether the standard 0.05 s to 300 h range or the -301 double range (0.1 s to 600 h) is needed.
• Check the load: 5 A at 250 VAC is the resistive rating, with 10 mA at 5 VDC as the minimum load.
• Pick the 8-pin socket type (front DIN-rail, back screw, PCB) and whether a finger-safe P2CF-08-E is required.
• State if the transistor output of H3CR-A8S is a better fit for PLC-style loads.

Installation, commissioning and maintenance of H3CR-A8

Fit the H3CR-A8 into its 8-pin socket and secure it with the Y92H-7 or Y92H-8 clips on panel-mounted bases. Wire the supply to the terminals shown in the datasheet terminal arrangement, and keep supply wiring away from low-level signal cables because the timer does not tolerate inverter output as a supply.

• Set the time unit and full-scale selectors first, then the operating mode, and finally the fine value on the dial.
• Test with the dial turned below zero to confirm output wiring without waiting for the full time.
• Check that the supply stays within 85% to 110% of rating; 12 VDC units need 90% to 110%.
• Annual maintenance is limited to inspecting the socket for loose screws and discolouration and confirming that the relay contacts still switch the connected load.
• Keep a spare of the same voltage version, as a replacement must match the supply exactly.

Typical H3CR-A8 applications in Oman and the GCC

In Oman and the GCC the H3CR-A8 is used mostly in compact motor-control cabinets and auxiliary panels where a basic delay is required. Examples include delayed start of cooling-tower and ventilation fans after a main contactor closes, staggered start of pump skids on a shared feeder, and flasher circuits for beacon and alarm lamps. Its 24 to 48 VDC version suits skid and cabin panels fed from a battery or DC bus.

Panels in Gulf conditions see high ambient temperature, so the operating limit of 55°C and the 35% to 85% humidity window should be compared with the actual cabinet temperature. Ventilated cabinets, or a sunshade over outdoor enclosures, help keep the timer within its rated limits in summer.

H3CR family compared with H3CR-A8

The table places H3CR-A8 next to the other timers in the same H3CR catalogue so you can confirm that you are asking for the right base model before the voltage is added.

Information to send with an RFQ for H3CR-A8

• Part number H3CR-A8 and quantity.
• Supply voltage and frequency, AC or DC.
• Required time range and operating mode.
• Load type, voltage and current on the output contact.
• Socket and accessory needs (P3G-08, P2CF-08, cover, clip).
• Delivery location in Oman or the GCC.

Documents and quotation

A datasheet for the H3CR series is attached on this page, covering the model legend, time ranges, ratings, timing charts, dimensions and safety precautions for H3CR-A8 and its siblings. Please read the precautions section before wiring.

Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer. Send the part number H3CR-A8, the supply voltage and the quantity, and we will confirm availability and lead time for Oman and the GCC.