Schneider Electric CAD32D7 TeSys D Relay 3NO+2NC 42V AC

CAD32D7 TeSys D control relay: what the part number tells you

The CAD32D7 is a Schneider Electric TeSys D control relay: TeSys D control relay, 3 NO + 2 NC, up to 690 V, 42 V AC standard coil. In plain terms it is a contactor-style relay with three normally open and two normally closed contacts, designed for control circuits rather than motor power, and its coil is rated 42 V AC 50/60 Hz. Seven Star LLC supplies the CAD32D7 in Oman and the GCC as an independent supplier based in Muscat.

Reading the code against the datasheet: CAD is the TeSys D control relay series, 32 gives the 3 NO + 2 NC contact arrangement (five poles in both cases), and the ending D7 stands for the 42 V AC 50/60 Hz coil that the datasheet lists for this reference. Neighbouring references differ only in the coil voltage or type, so the complete code decides whether the relay will fit your control supply.

Technical specifications of the CAD32D7

Coil, operating window and supply sizing for the CAD32D7

The coil is the one part that distinguishes the CAD32D7 from its siblings, so it deserves the closest reading.

The 42 V AC coil is a less common voltage, found on machines and cabinets built around a 42 V control winding, for instance imported equipment wired to European or Asian machine-tool practice. It keeps the control circuit in the extra-low-voltage range while giving a lower current than a 24 V coil. With 70 VA inrush and 8 VA hold-in at 50 Hz, the coil draws about 1.7 A at pull-in and 0.19 A when held in.

The operating window of 0.8 to 1.1 Uc at 50 Hz is about 33.6 to 46.2 V and, at 60 Hz, 35.7 to 46.2 V. The drop-out band of 0.3 to 0.6 Uc is about 12.6 to 25.2 V. Because 42 V is not a standard supply in most Omani panels, this reference is nearly always a like-for-like replacement for an existing relay in imported machinery, and the nameplate of the old relay is the best proof that 42 V is really what the control transformer delivers.

Calculated from the datasheet, the 42 V AC 50/60 Hz coil of the CAD32D7 has an operational window of 33.6 to 46.2 V at 50 Hz (0.8 to 1.1 Uc), from 35.7 V at 60 Hz, and it drops out at 12.6 to 25.2 V (0.3 to 0.6 Uc). The datasheet gives 70 VA inrush and 8 VA hold-in at 50 Hz, which corresponds to about 1.67 A at pull-in and 190 mA when held in at the nominal voltage. These are indicative figures worked out from the stated power and voltage, and they are meant for supply sizing, not as guaranteed current ratings.

Contact arrangement of the CAD32D7: three normally open and two normally closed contacts

The 3 NO + 2 NC configuration is the most flexible arrangement for a control relay, because the normally closed pair lets one device take part in interlocking and fault-reset circuits as well as repeating a signal. The datasheet lists a non-overlap time of 1.5 ms on energisation and 1.5 ms on de-energisation between the normally closed and normally open contacts, so that the two groups do not conduct at the same time during a transition.

Use the normally closed contacts for permissive and interlock loops that must fall away on operation, such as stopping a second starter while the first is running, or for a healthy-state signal that drops out when the relay operates. The normally open contacts are available to repeat start, run and trip signals. If a circuit needs more than three normally open contacts and no normally closed ones, the 5 NO version of the same family is the better match.

Contact data from the datasheet apply to all five poles: 10 A conventional thermal current at 60 °C, utilisation categories AC-15, AC-14 and DC-13, a rated operational voltage up to 690 V AC, and a minimum switching capability of 17 V and 5 mA, which makes the contacts suitable for low-level signals as well as for 24 V PLC inputs.

Where the CAD32D7 sits in the CAD32 family

The CAD32D7 is one member of a family of TeSys D control relays that share the housing, the contact data and the mounting. Only the coil voltage and type change from one reference to the next, together with the contact arrangement: the CAD32 series is 3 NO + 2 NC and the CAD50 series is 5 NO. The table lists the CAD32 references we are asked for most.

If the supply is not in the table, ask us; the CAD50 series has the other contact arrangement. AC-coil versions are 84 mm deep and DC-coil versions 93 mm, which matters in a shallow enclosure.

Selection checklist for the CAD32D7

• Coil: 42 V AC 50/60 Hz, confirmed from the supply drawing or the nameplate of the relay being replaced.
• Contacts: three normally open and two normally closed contacts, matched to the interlock and signalling circuits.
• Supply sizing: about 1.67 A at pull-in and 190 mA held in (derived from the datasheet power).
• Window: operates within 33.6 to 46.2 V at 50 Hz (0.8 to 1.1 Uc), from 35.7 V at 60 Hz and releases at 12.6 to 25.2 V (0.3 to 0.6 Uc).
• Contact load of the CAD32D7: 10 A thermal, AC-15, AC-14 or DC-13 duties; use a contactor for motor-power loads.
• Space: 77 mm high, 45 mm wide and 84 mm deep.
• Environment: operation up to 60 °C, up to 70 °C with derating; storage -60 to 80 °C.
• Type: AC and DC coils of the same voltage are different references; do not mix them.

Mounting, wiring and service life of the CAD32D7

Mount the CAD32D7 on a 35 mm DIN rail or on a plate; the datasheet lists both. It measures 77 mm x 45 mm x 84 mm and weighs 0.58 kg, so allow space for the wires to bend at the terminals and for air to circulate around the housing. Tighten the screw-clamp terminals to 1.7 N.m with a Philips No 2, Pozidriv No 2 or 6 mm flat screwdriver, and do not exceed the cable sizes of 1 to 4 mm² per terminal listed in the datasheet.

Commissioning is simple: energise the coil at nominal voltage, verify that all five poles move together, and check the contact action with a meter before connecting the field loads. The mechanical durability is 30 million cycles and the maximum operating rate is 180 cycles per minute, so in normal control duty there is no routine wear item to schedule. In a dusty site, clean the panel and check terminal tightness during planned shutdowns, because loose terminals, more often than the relay itself, cause intermittent faults.

Where the CAD32D7 is used in Oman and the GCC

Low-voltage AC coils are used where a control transformer separates the relay circuit from the mains. In the GCC they appear mostly in machine panels, HVAC and pump control cabinets built by international manufacturers, where a 24, 42 or 48 V winding supplies relays, pilot lamps and solenoid valves. Here the relay is a repeater and interlock element between a controller output and field loads or drives.

For the CAD32D7, that means three normally open and two normally closed contacts from one 42 V AC 50/60 Hz command, sitting next to LC1D contactors of the same TeSys D family on the same rail.

Information to send with an RFQ for the CAD32D7

• Full reference CAD32D7 and the quantity
• The coil voltage and type seen on the supply drawing or on the old relay nameplate
• The load or circuit each contact will switch (voltage, current, signal level)
• Panel or machine the relay must fit, and whether it is a spare, a replacement or a new installation
• Delivery location in Oman or the GCC and the date required

Documents and quotation

A datasheet for this product is attached on this page. It lists the electrical, mechanical and environmental data summarised above, and it is worth reading beside the panel drawing before you order.

Send us the part number, quantity and application and we will confirm availability and a quotation. Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer.